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AIIMS PREVIOUS YEARS ZOOLOGY Questions & Solutions

CHAPTER-23: Reproduction in Organisms

MULTIPLE CHOICE QUESTIONS

Based on cellular mechanisms there are two major types of regeneration found in the animals. Which one of the following is the correct example of the type mentioned? [2005]
(a) Morphallaxis – Regeneration of two transversely cut equal pieces of a Hydra into two small Hydras.
(b) Epimorphosis – Replacement of old and dead erythrocytes by the new ones.
(c) Morphallaxis – Healing up of a wound in the skin.
(d) Epimorphosis – Regeneration of crushed and filtered out pieces of a Planaria into as many new Planarians. from chapter 25

Which form of reproduction is correctly matched? [2007]
(a) Euglena → transverse binary fission
(b) Paramecium → longitudinal binary fission
(c) Amoeba → multiple fission
(d) Plasmodium → binary fission

Which reproductive adaptation is characteristic of most terrestrial vertebrates but not of most aquatic vertebrates? [2009]
(a) External fertilization
(b) Internal fertilization
(c) Motile gametes
(d) External development

Identify the events (A, B, D and E) in life of general reproduction-[2015]

(a) A-Gamete transfer, B-Gametogeneis, D-Zygote formation, E-Embryogenesis
(b) A-Gametogeneis, B-Gamete transfer, D-Zygote formation, E-Embryogenesis
(c) A-Gametogeneis, B-Zygote formation, D-Gamete transfer, E-Embryogenesis
(d) A-Gametogeneis, B-Gamete transfer, D-Embryogenesis, E-Zygote formation.

Which of the following statements is incorrect ?
(i) Bamboo species flower only once in their life time, generally after 50-100 years and produce large number of fruits and die.
(ii) In animals, the juvenile phase is followed by morphological and physiological changes prior to active reproductive behaviour.
(iii) The reproductive phase is of same duration in all organisms.
(iv) Juvenile phase is the period of growth between the birth of an individual till it reaches reproductive maturity. [2016]
(a) Only (i) (b) Only (ii)
(c) Only (iii) (d) Only (iv)

In a practical test, a student has to identify the organisms in which syngamy does not occur. In those organisms the female gamete undergoes development to form new organisms without fertilization. This phenomenon is called “X”. Identify the organisms and the phenomenon
“X”. [2017]
(a) Frog, Parthenogenesis
(b) Lizards, Gametogenesis
(c) Rotifers, Embryogenesis
(d) Honeybee, Parthenogenesis

ASSERTION REASON QUESTIONS

Directions for (Q. 1) : Each of these questions contains an Assertion followed by Reason. Read them carefully and answer the question on the basis of
following options. You have to select the one that best describes the two statements.
(a) If both Assertion and Reason are correct and Reason is the correct explanation of Assertion.
(b) If both Assertion and Reason are correct, but Reason is not the correct explanation of Assertion.
(c) If Assertion is correct but Reason is incorrect.
(d) If both the Assertion and Reason are incorrect.

1-Assertion : Leaves of Bryophyllum, Begonia help in vegetative multiplication.
Reason : Leaves of these plants possess adventitious buds. [2014]

CHAPTER-24: Sexual Reproduction in Flowering Plants

MULTIPLE CHOICE QUESTIONS

Asexual reproduction is called as [1997]
(a) apomixis (b) fragmentation
(c) self fertilization (d) cross fertilization

Pollination by snail and slug is called as [1998]
(a) entomophilous
(b) malacophilous
(c) ornithophilous
(d) chiropterophilous

In angiosperm, the endosperm is [1998]
(a) diploid (b) triploid
(c) haploid (d) polyploid

Female gametophyte of angiosperm is [1999]
(a) 7 celled (b) 8 celled
(c) 11 celled (d) 5 celled

Anemophilous flowers have [1999]
(a) sessile stigma
(b) small, smooth stigma
(c) coloured and scented flowers
(d) large feathery stigma

Growth of pollen tube towards embryo is [2000]
(a) geotropism (b) chemotaxis
(c) phototaxis (d) thigmotaxis

Which of the following statement is true?[2000]
(a) Spores are gametes
(b) Spores and gametes are diploid
(c) Gametes are always haploid
(d) Spores are always diploid

Which part of embryo comes out first during seed germination ? [2001]
(a) Radicle (b) Plumule
(c) Hypocotyl (d) Epicotyl

Xenia refers to [2002]
(a) effect of pollen on endosperm
(b) effect of pollen on stems
(c) effect of pollen on taste of fruits
(d) effect of pollen on vascular tissue

Ploidy of ovum of angiosperms is [2002]
(a) haploid (b) diploid
(c) triploid (d) polyploid

Pollen grains are able to withstand extremes of temperature and dessication because their exine is composed of [2003]
(a) cutin (b) suberin
(c) sporopollenin (d) callose

The pollen tube usually enters the embryo sac
(a) between the egg cell and synergid[2004]
(b) by directly penetrating the egg
(c) between one synergid and antipodal cell
(d) by knocking off the antipodal cells

Double fertilization involves [2005]
(a) fertilization of egg by two male gametes
(b) fertilization of two eggs in the same embryo sac by two sperms brought by one pollen tube
(c) fertilization of the egg and the central cell by two sperms brought by different pollen tubes
(d) fertilization of the egg and the central cell by two sperms brought by the same pollen tube

In which one of the following combinations (a – d) the number of chromosomes of the present day hexaploid wheat is correctly represented?
[2006]

Apomixis is [2007]
(a) formation of seeds by fusion of gametes.
(b) formation of seeds without syngamy and meiosis.
(c) formation of seeds with syngamy but no meiosis.
(d) None of the above

The plant part which consists of two generations one within the other, is [2008]
(a) germinated pollen grain
(b) embryo
(c) unfertilized ovule
(d) seed

Chasmogamy refers to the condition where [2012]
(a) Flowers remains closed
(b) Flowers are absent
(c) Flowers are open
(d) Flower are gamopetalous

What is common between vegetative reproduction and apomixis? [2013]
(a) Both are applicable to only dicot plants
(b) Both bypass the flowering phase
(c) Both occur round the year
(d) Both produces progeny identical to the parent

Emasculation is not required when flowers are [2013]
(a) bisexual (b) intersexual
(c) unisexual (d) either (a) or (b)

Geitonogamy involves:
(a) fertilization of a flower by the pollen from another flower of the same plant.
(b) fertilization of a flower by the pollen from the same flower.
(c) fertilization of a flower by the pollen from a flower of another plant in the same population.
(d) fertilization of a flower by the pollen from a flower of another plant belonging to a distant population. [2014]

Which of the following statement is correct? [2016]
(a) Sporopollenin can withstand high temperatures but not strong acids.
(b) Sporopollenin can be degraded by enzymes.
(c) Sporopollenin is made up of inorganic materials.
(d) Sporopollenin can withstand high temperature as well as strong acids and alkalis.

ASSERTION REASON QUESTIONS

Directions for (Qs.1-3) : These questions consist of two statements, each printed as Assertion and Reason. While answering these questions, you are
required to choose any one of the following five responses.
(a) If both Assertion and Reason are correct and the Reason is a correct explanation of the Assertion.
(b) If both Assertion and Reason are correct but Reason is not a correct explanation of the Assertion.
(c) If the Assertion is correct but Reason is incorrect.
(d) If both the Assertion and Reason are incorrect.
(e) If the Assertion is incorrect but the Reason is correct.

1-Assertion : If pollen mother cells has 42 chromosomes, the pollen has only 21 chromosomes.
Reason : Pollens are formed after meiosis in pollen mother cell. [1997]

2-Assertion: The megaspore mother cell divide mitotically to produce four spores.
Reason: Megaspore mother cells are diploid and megaspore is haploid. [2002]

3-Assertion : Insects visit flower to gather honey.
Reason : Attraction of flowers prevents the insects from damaging other parts of the plant. [2004]

Directions for (Qs. 1-4) : Each of these questions contains an Assertion followed by Reason. Read them carefully and answer the question on the basis of following options. You have to select the one that
best describes the two statements.
(a) If both Assertion and Reason are correct and Reason is the correct explanation of Assertion.
(b) If both Assertion and Reason are correct, but Reason is not the correct explanation of Assertion.
(c) If Assertion is correct but Reason is incorrect.
(d) If both the Assertion and Reason are incorrect.

1-Assertion : Pollen mother cells (PMCs) are the first male gametophytic cells. [2009]
Reason : Each PMC gives rise to two pollens.

2-Assertion : Chasmogamous flowers require pollinating agents.
Reason : Cleistogamous flowers do not expose their sex organs. [2012]

3-Assertion : Double fertilization is characteristic feature of angiospersms.
Reason : Double fertilization involves two fusions. [2016]

4-Assertion : Endosperm is a nutritive tissue and it is triploid.
Reason: Endosperm is formed by fusion of secondary nucleus to second male gamete. It is used by developing embryo. [1998, 2017]

CHAPTER-25: Human Reproduction

MULTIPLE CHOICE QUESTIONS

Prostate gland secretion helps in formation of
(a) larva (b) semen [1997]
(b) cocoon (c) none of these

Immediately after ovulation, the mammalian egg is covered by a membrane called as [1998]
(a) chorion (b) corona radiata
(c) zona pellucida (d) none of these

The extra-embryonic membranes of mammalian embryo are derived from [1999]
(a) trophoblast (b) follicle cells
(c) inner cell mass (d) formative cells

Acrosome of sperm is formed by [1999]
(a) nucleus (b) golgi bodies
(c) lysosome (d) E. R.

Cumulus covers [1999]
(a) ovary (b) ovum
(c) embryo (d) sperm

Cessation of menstrual cycle in women is called
(a) menopause (b) lactation [2001]
(c) ovulation (d) parturition

Both corpus luteum and macula lutea are [2003]
(a) found in human ovaries
(b) a source of hormones
(c) characterized by a yellow colour
(d) contributory in maintaining pregnancy

The early human embryo distinctly possesses [2003]
(a) gills
(b) gill slits
(c) external ear (pinna)
(d) eyebrows

The phase of menstrual cycle in humans that lasts for 7-8 days, is [2003]
(a) follicular phase (b) ovulatory phase
(c) luteal phase (d) menstruation

Which one of the following statements with regard to embryonic development in humans is correct? [2003]
(a) Cleavage divisions bring about considerable increase in the mass of protoplasm.
(b) In the second cleavage division, one of the two blastomeres usually divides a little sooner than the second.
(c) With more cleavage divisions, the resultant blastomeres become larger and larger.
(d) Cleavage division results in a hollow ball of cells called morula.

Women who consumed the drug thalidomide for relief from vomiting during early months of pregnancy gave birth to children with [2004]
(a) no spleen
(b) hare-lip
(c) extra fingers and toes
(d) under developed limbs

A cross section at the midpoint of the middle piece of a human sperm will show [2005]
(a) centriole, mitochondria and 9 + 2 arrangement of microtubules.
(b) centriole and mitochondria.
(c) mitochondria and 9 + 2 arrangement of microtubules.
(d) 9 + 2 arrangement of microtubules only

Which one of the following events is correctly matched with the time period in a normal menstrual cycle? [2005]
(a) Release of egg : 5th day
(b) Endometrium regenerates : 5-10 days
(c) Endometrium secretes nutrients for implantation : 11-18 days
(d) Rise in progesterone level : 1-15 days

Which of the following is true regarding sperm? [2007]
(a) Fertilizin: For penetrating egg membrane
(b) Hyalurodinase: For penetrating egg membrane
(c) Acrosin: Dissolves corona radiata
(d) Capacitation: Takes place in penis

Both corpus luteum and macula lutea are [2008]
(a) found in human ovaries
(b) a source of hormones
(c) characterized by a yellow colour
(d) contributory in maintaining pregnancy

gametes produced from one male primary sex cell to the number of gametes produced from one female primary sex cell? [2009]
(a) 1:3 (b) 1:4
(c) 3:1 (d) 4:1

Corpus luteum is a mass of cells found in[2010]
(a) brain (b) ovary
(c) pancreas (d) spleen

Cells of leydig are found in [1997, 2011]
(a) Testes of frog (b) Testes of rabbit
(c) Kidney of frog (d) Kidney of rabbit

Meroblastic cleavage refers to which type of division of egg [2001, 2011]
(a) Complete (b) Spiral
(c) Incomplete (d) Horizontal

Which of the following organ is differentiated first during development? [2012]
(a) Heart (b) Skin
(c) Brain (d) Neural tube

The correct sequence of spermatogenetic stages leading to the formation of sperms in a mature human testis is: [2013]
(a) spermatogonia-spermatid-spermatocytesperms
(b) spermatocyte-spermatogonia-spermatidsperms
(c) spermatogonia-spermatocyte-spermatidsperms
(d) spermatid-spermatocyte-spermatogoniasperms

All of the following statements concerning pregnancy are accurate EXCEPT [2015]
(a) the detection of human chorionic gonadotropin in the urine forms the basis for pregnancy tests.
(b) the cyclic release of pituitary gonadotropins and ovarian steroids is
continued.
(c) the mammary gland tissue of the pregnant woman is stimulated to develop by placental hormones.
(d) the corpus luteum of pregnancy maintains the uterus until the placenta is well established.

The following graph of relative concentrations of the four hormones present in the blood plasma of a woman during her menstrual cycle. Identify the hormones. [2015]

Ejaculation of human male contains about 200 – 300 million sperms, of which for normal fertility _ % sperms must have normal shape and size and at least ____% must show energetic motility. [2016]
(a) 40, 60 (b) 50, 50
(c) 60, 40 (d) 30, 70

The given figure shows the human foetus within the uterus with few structures marked as A, B, C and D.

Which of the following options shows the correct labeling? [2016]
(a) A → Umbilical cord with its veins, B → Chorionic villi, C → Antrum, D → Plug of mucus in cervix
(b) A → Umbilical cord with its vessels, B → Fimbriae, C → Oocyte, D → Plug of mucus in vagina
(c) A → Umbilical cord with its vessels, B → Placental villi, C → Yolk sac, D → Plug of mucus in cervix
(d) A → Umbilical cord with its veins, B → Placental villi, C → Trophoblast,
D → Plug of mucus in vagina [2016]

The figure given below shows the sectional view of ovary. Select the option which gives correct identification of marked structure (A to D) and its feature. [2017]

(a) A: Primary follicle, it is also called gamete mother cell.
(b) B: Corpus luteum, it cannot be formed and added after birth.
(c) C: Grafian follicle, mature follicle which ruptures to release secondary oocyte.
(d) D: Tertiary follicle, a large number of this follicle degenerates during the phase from birth to puberty.

ASSERTION REASON QUESTIONS

Directions for (Qs. 1-5) : These questions consist of two statements, each printed as Assertion and Reason. While answering these questions, you are
required to choose any one of the following five responses.
(a) If both Assertion and Reason are correct and the Reason is a correct explanation of the Assertion.
(b) If both Assertion and Reason are correct but Reason is not a correct explanation of the Assertion.
(c) If the Assertion is correct but Reason is incorrect.
(d) If both the Assertion and Reason are incorrect.
(e) If the Assertion is incorrect but the Reason is correct.

1-Assertion : During fertilization only head of spermatozoa enters egg.
Reason : If several spermatozoa hit the egg at same time, all can enter the egg. [1997]

2-Assertion : In morula stage, cells divide without increase in size.
Reason : Zona pellucida remains undivided till cleavage is complete. [1997]

3-Assertion : Death is one of the important regulatory process on earth.
Reason : It avoids over-crowding caused by continuous reproduction. [2002]

4-Assertion : Old age is not an illness. It is a continuation of life with decreasing capacity for adaptation.
Reason : Cessation of mitosis is a normal genetically programmed event. [2003]

5-Assertion : Senescence is the time when age associated defects are manifested. [2005]
Reason : Certain genes may be undergoing sequential switching on and off during one’s life.

Directions for (Qs. 32-38) : Each of these questions contains an Assertion followed by Reason. Read them carefully and answer the question on the basis of following options. You have to select the one that best describes the two statements.
(a) If both Assertion and Reason are correct and Reason is the correct explanation of Assertion.
(b) If both Assertion and Reason are correct, but Reason is not the correct explanation of Assertion.
(c) If Assertion is correct but Reason is incorrect.
(d) If both the Assertion and Reason are incorrect.

1-Assertion : Corpus luteum degenerates in the absence of fertilization.[2009]
Reason : Progesterone level decreases.

2-Assertion : Clitoris is not remnant of penis in females. [2009]
Reason : It also has high blood supply and erectile tissue.

3-Assertion : Mammalian ova produces hyaluronidase. [2009]
Reason : The eggs of mammal are microlecithal and telolecithal.

4-Assertion : Head of sperm consists of acrosome and mitochondria.
Reason : Acrosome contains spiral row of mitochondria

5-Assertion : Females have less stature than males after puberty.
Reason : This happens because of the presence of hCG in the blood of females. [2014]

6-Assertion : Testicular lobules are the compartments present in testis.
Reason : These lobules are involved in the process of fertilization. [2016]

7-Assertion : Interstitial cell is present in the region outside the seminiferous tubule called interstitial spaces.
Reason : Interstitial cells provide nutrition to the sertoli cells. [2016, 2017]

CHAPTER-26:Reproductive Health

MULTIPLE CHOICE QUESTIONS

GIFT is [2009]
(a) transfer of a sperm in fallopian tube of a female with the help of injections.
(b) transfer of a zygote fertilized in vitro in the fallopian tube of female incapable to conceive.
(c) transfer of an ovum collected from a donor into another females fallopian tube who can’t produce an ovum but can provide a good environment for further development.
(d) embryo is developed in vitro and then transferred into female’s tract.

What is the function of copper-T ?
(a) Checks mutation [2012]
(b) Stops fertilization
(c) Stops zygote formation
(d) Stops oblituation of blastocoel

Progestasert and LNG-20 are [2013]
(a) Implants
(b) Copper releasing IUDs
(c) Non-medicated IUDs
(d) Hormone releasing IUDs

What is the figure given below showing in particular ?

(a) Ovarian cancer (b) Uterine cancer
(c) Tubectomy (d) Vasectomy

Match Column -I with Column – II. [2015]
Column I ________Column II
Method ………………Mode of Action
A. The pill…………… I. Prevents sperms reaching cervix
B. Condom …………..II. Prevents implantation
C. Vasectomy………. III. Prevents ovulation
D. Copper T ………….IV. Semen contains no sperms
(a) A – III; B – I; C – IV; D – II
(b) A – IV; B – I; C – II; D – III
(c) A – III; B – IV; C – I; D – II
(d) A – II; B – III; C – I; D – IV

Select the correct match of the techniques given in column I with its feature given in column II.

(a) A – V; B – IV; C – I; D – III; E – IV
(b) A – I; B – II; C – III; D – IV; E – V
(c) A – III; B – V; C – II; D – IV; E – I
(d) A – III; B – I; C – V; D – II; E – IV

ASSERTION REASON QUESTIONS

Directions for (Qs. 7-9) : Each of these questions contains an Assertion followed by Reason. Read them carefully and answer the question on the basis of following options. You have to select the one that
best describes the two statements.
(a) If both Assertion and Reason are correct and Reason is the correct explanation of Assertion.
(b) If both Assertion and Reason are correct, but Reason is not the correct explanation of Assertion.
(c) If Assertion is correct but Reason is incorrect.
(d) If both the Assertion and Reason are incorrect.

1-Assertion : Cu-T and Cu-7 do not suppresses sperm-motility.
Reason : Hormones released by them affect sperm motility. [2009]

2-Assertion : HIV infection can be avoided by use of condoms.
Reason : Condoms secrete anti-viral interferons. [2014]

3-Assertion : Copper-T is an effective contraceptive device in human females.
Reason : Copper-T prevents passage of sperms from vagina upwards into fallopian tubes. [2011, 2014]

CHAPTER-27: Principles of Inheritance and Variation

MULTIPLE CHOICE QUESTIONS

The formation of multivalents at meiosis in diploid organism is due to [1998]
(a) monosomy
(b) deletion
(c) inversion
(d) reciprocal translocation

If a homozygous tall plant is crossed with homozygous dwarf plant, the offsprings will be[1999]
(a) all tall plants (b) all dwarf plants
(c) half tall plants (d) half dwarf plants

XO chromosomal abnormality in humans causes [1999]
(a) Turner’s syndrome
(b) Down’s syndrome
(c) Patau’s syndrome
(d) Klinefelter’s syndrome

Polygenic genes show [2000]
(a) similar genotype
(b) different phenotype
(c) different karyotype
(d) different genotype

Which disease has XXY chromosome constitution?
(a) Down’s syndrome [2000]
(b) Turner’s syndrome
(c) Klinefelter’s syndrome
(d) Okazaki syndrome

Barr-body in mammals represents [2001]
(a) One of the two X chromosomes in somatic cells of females.
(b) All heterochromatin of male & female cells.
(c) Y chromosomes of male.
(d) All heterochromatin of female cells

Discontinuous variations are [2001]
(a) essential features
(b) acquired characters
(c) non-essential changes
(d) mutations

Mirabilis jalapa shows [2001]
(a) codominance
(b) incomplete dominance
(c) dominance
(d) complementary genes

Frame shift mutation occurs when [2002]
(a) base is added
(b) base is deleted
(c) base is added or deleted
(d) none of the above

Pure line breed refers to [2002]
(a) homozygosity (b) heterozygosity
(c) linkage (d) both b & c

If a homozygous red flowered plant is crossed with a homozygous white flowered plant, the offsprings would be [2002]
(a) all red flowered
(b) half red flowered
(c) half white flowered
(d) all white flowered

Genes of which one of the following is present exclusively on the X-chromosome in humans? [2003]
(a) Baldness
(b) Red-green colour blindness
(c) Facial hair/moustaches in males
(d) Night blindness

Given below is a pedigree chart of a family with five children. It shows the inheritance of attached earlobes as opposed to the free ones. The squares
represent the male individuals and circles the female individuals. Which one of the following conclusions drawn is correct? [2004]

(a) The parents are homozygous recessive.
(b) The trait is Y-linked.
(c) The parents are homozygous dominant.
(d) The parents are heterozygous

Given below is a representation of a kind of chromosomal mutation. What is the kind of mutation represented?

(a) deletion
(b) duplication
(c) inversion
(d) reciprocal translocation

How many different types of gametes can be formed by F1 progeny, resulting from the following cross Tt × Rr? [2004]
(a) 4 (b) 8
(c) 27 (d) 64

Grain colour in wheat is determined by three pairs of polygene. Following the cross AABBCC (dark colour) × aabbcc (light colour), in F2 generation
what proportion of the progeny is likely to resemble either parent? [2005]
(a) Half (b) Less than 5 percent
(c) One third (d) None of these

Primary source of allelic variation is [2005]
(a) independent assortment
(b) recombination
(c) mutation
(d) polyploidy

Given below is a pedigree chart showing the inheritance of a certain sex-linked trait in humans.

The trait traced in the above pedigree chart is [2005]
(a) dominant X-linked
(b) recessive X-linked
(c) dominant Y-linked
(d) recessive Y-linked

The “Cri-du-Chat” syndrome is caused by change in chromosome structure involving [2005]
(a) deletion (b) duplication
(c) inversion (d) translocation

Given below is a highly simplified representation of the human sex chromosomes from a karyotype. [2006]

The genes a and b could be of
(a) colour blindness and body height
(b) attached ear lobe and Rhesus blood group
(c) haemophilia and red-green colour blindness
(d) phenylketonuria and haemophilia

In India, we find mangoes with different flavours, colours, fibre content, sugar content and even shelf-life. The large variation is on account of
[2006]
(a) species diversity
(b) induced mutations
(c) genetic diversity
(d) hybridization

Which one of the following pairs of features is a good example of polygenic inheritance? [2006]
(a) Human height and skin colour.
(b) ABO blood group in humans and flower colour of Mirabilis jalapa.
(c) Hair pigment of mouse and tonque rolling in humans.
(d) Human eye colour and sickle cell anaemia

Gene which suppresses other gene’s activity but does not lie on the same locus is called as [2007]
(a) epistatic (b) supplementary
(c) hypostatic (d) codominant

XO-chromosomal abnormality in human beings causes [2007]
(a) Turner’s syndrome
(b) Down’s syndrome
(c) Klinefelter’s syndrome
(d) none of the above

A normal woman whose father was colour blind, is married to a normal man. The sons would be [2008]
(a) 75% colour blind
(b) 50% colour blind
(c) all normal
(d) all colour blind

Mating of an organism to a double recessive in order to determine whether it is homozygous or heterozygous for a character under consideration is called [2008]
(a) reciprocal cross (b) test cross
(c) dihybrid cross (d) back cross

Bird females have chromosome arrangement as [2009]
(a) XY (b) XO
(c) WZ (d) WW

Gene pool is referred to [2009]
(a) the genetic drift caused in a population
(b) aggregate of all genes and their alleles in a population.
(c) deletion of non essential genes.
(d) induce cell division

Mother and father both have blood group ‘A’. They have two children one with blood group ‘O’ and second one with blood group ‘A’.
They have [2009]
(a) mother has homozygotic gene father has heterozygote I’A IA.
(b) both are homozygotic ( IA IA ).
(c) mother is heterozygotic ( IAi ) and father is homozygotic ( IA IA ).
(d) both are heterozygotic (IAi).

When one gene controls two or more different characters simultaneously, the phenomenon is called [2010]
(a) apomixis (b) pleiotropy
(c) polyploidy (d) polyteny

Three children in a family have blood types O, AB and B respectively. What are the genotypes of their parents? [2013]
(a) IAi and IBi (b) I AIB and i i
(c) IBIB and IAIA (d) IAIA and IBi

If both parents are carriers for thalassemia, which is an autosomal recessive disorder, what are the chances of pregnancy resulting in an affected child? [2014]
(a) 50% (b) 25%
(c) 100% (d) no chance

In Huntington’s disease, the unaffected persons are homozygous for normal allele h. The following is erroneous because [2015]

(a) it shows both male and female affected by Huntingtons disease
(b) either person 6 or 7 should have the disease, if individual 11 shows the disease.
(c) at least one of the 2 children (8, 9) should have the disease
(d) all of these

The experiment shown in the given figure has been carried out by Morgan to show the phenomenon of linkage and recombination. If in
cross I, genes are tightly linked and in cross II, genes are loosely linked then what will be the percentage of recombinants produced in cross I
and cross II respectively?

(a) 98.7% and 62.8%
(b) 1.3% and 37.2%
(c) 37.2 and 1.3%
(d) 62.8% and 98.7%

ASSERTION REASON QUESTIONS

Directions for (Qs. 1-4) : These questions consist of two statements, each printed as Assertion and Reason. While answering these questions, you are
required to choose any one of the following five responses.
(a) If both Assertion and Reason are correct and the Reason is a correct explanation of the Assertion.
(b) If both Assertion and Reason are correct but Reason is not a correct explanation of the Assertion.
(c) If the Assertion is correct but Reason is incorrect.
(d) If both the Assertion and Reason are incorrect.
(e) If the Assertion is incorrect but the Reason is correct.

1-Assertion : The genetic complement of an organism is called genotype.
Reason : Genotype is the type of hereditary properties of an organism. [1999]

2-Assertion : Phenylketonuria is a recessive hereditary disease caused by body’s failure to oxidize an amino acid phenylalanine to tyrosine,
because of a defective enzyme.
Reason : It results in the presence of phenylalanine acid in urine. [2000]

3-Assertion : In humans, the gamete contributed by the male determines whether the child produced will be male or female.
Reason : Sex in humans is a polygenic trait depending upon a cumulative effect of some genes on X-chromosome and some on Y-chromosome.

4-Assertion : Haemophilia is a recessive sex linked disease.
Reason : Haemophilia occurs due to mutation of a structural gene on chromosome 15. [2007]

Directions for (Qs.1-6) : Each of these questions contains an Assertion followed by Reason. Read them carefully and answer the question on the basis of following options. You have to select the one that best describes the two statements. (a) If both Assertion and Reason are correct and
Reason is the correct explanation of Assertion.
(b) If both Assertion and Reason are correct, but Reason is not the correct explanation of Assertion.
(c) If Assertion is correct but Reason is incorrect.
(d) If both the Assertion and Reason are incorrect.

1-Assertion : Persons suffering from haemophilia fail to produce blood clotting factor VIII.
Reason : Prothrombin producing platelets in such persons are found in very low concentration. [2008]

2-Assertion : In case of incomplete linkage, linked gene show new combination along with parental combination.
Reason : In case of incomplete linkage, linked genes are separated by crossing over. [2010]

3-Assertion: Aneuploidy may be of hypoploidy or hyperploidy type.
Reason: Monosomy lacks one pair of chromosomes. [2011]

4-Assertion : Cross of F1 individual with recessive homozygous parent is test cross.
Reason : No recessive individual are obtained in the monohybrid test cross. [2012]

5-Assertion : In Mirabilis, selfing of F1 F1 pink flower plants produces same phenotypic & genotypic ratio.
Reason : Flower colour gene shows incomplete dominance. [2014]

6-Assertion : In humans, the gamete contributed by the male determines whether the child produced will be male or female.
Reason : Sex in humans is a polygenic trait depending upon a cumulative effect of some genes on X-chromosome and some on Y-chromosome. [2015, 2017]

CHAPTER-28:Molecular Basis of Inheritance

MULTIPLE CHOICE QUESTIONS

The process through which the amount of DNA, RNA and protein can be known at a time is called [1997]
(a) autoradiography
(b) tissue culture
(c) cellular fractioning
(d) phase contrast microscopy

Balbiani rings are found in [1997]
(a) polysomes
(b) polytene chromosomes
(c) autosomes
(d) nonsense chromosomes

In DNA helix, cytosine is paired with guanine by [1997]
(a) covalent bond
(b) phosphate bond
(c) three hydrogen bonds
(d) two hydrogen bonds

Which RNAs pick up specific amino acid from amino acid pool in the cytoplasm to ribosome during protein synthesis ? [1998]
(a) tRNA (b) mRNA
(c) rRNA (d) hnRNA

The structure of DNA is [1998]
(a) linear (b) double helix
(c) single helix (d) triple helix

Transposon was discovered by [1998]
(a) Sutton (b) Strassburger
(c) Fischer (d) B.Mc Clintock

Root cell of wheat has 42 chromosomes. What would be the number of chromosomes in the synergid cell ? [1999]
(a) 7 (b) 14
(c) 21 (d) 28

Okazaki fragments form [2000]
(a) leading strand (b) lagging strand
(c) non-sense strand (d) senseful strand

Wobble hypothesis was given by [2002]
(a) F.H.C. Crick (b) Nirenberg
(c) Holley (d) Khorana

Which one of the following pairs of terms/names mean one and the same thing? [2003]
(a) Gene pool-genome
(b) Codon-gene
(c) Cistron-triplet
(d) DNA fingerprinting – DNA profiling

What is true about t-RNA? [2003]
(a) It binds with an amino acid at it 3′ end.
(b) It has five double stranded regions.
(c) It had a codon at one end which recognizes the anticodon on messenger RNA.
(d) It looks like clover leaf in the three dimensional structure.

Which one of the following codons codes for the same information as UGC? [2003]
(a) UGU (b) UGA
(c) UAG (d) UGG

During protein synthesis in an organism, at one point the process comes to a halt. Select the group of the three codons from the following, from which anyone of the three could bring about this halt. [2006]
(a) UUU, UCC, UAU (b) UUC, UUA, UAC
(c) UAG, UGA, UAA (d) UUG, UCA, UCG

The total number of nitrogenous bases in human genome is estimated to be about [2004, 2008]
(a) 3.5 million (b) 35 thousand
(c) 35 million (d) 3.1 billion

Which one of the following pairs is correctly matched with regard to the codon and the amino acid coded by it ? [2004, 2008]
(a) UUA-valine (b) AM-lysine
(c) AUG-cysteine (d) CCC-alanine

What is the error in above diagram? [2009]
(a) Arrows are wrongly depicted.
(b) Polarity is incorrect.
(c) Both arrows and polarity are incorrect.
(d) None of the above.

TATA box of eukaryotic promotor lies [2010]
(a) about 25 bp upstream of the transcription start site.
(b) about 50 bp upstream of the transcription start site.
(c) about 75 bp upstream of the transcription start site.
(d) about 200 bp upstream of the transcription start site.

Which one of the following correctly represents the manner of replication of DNA ? [2003, 2012]

Select the correct option: [2014]
Direction of RNA ____________Direction of reading of
synthesis the template DNA strand
(a) 5´—3´…………………………… 3´—5´
(b) 3´—5´……………………………. 5´—3´
(c) 5´—3´ ……………………………..5´—3´
(d) 3´—5´…………………………….. 3´—5´

Which one of the following represents a palindromic sequence in DNA? [2014]
(a) 5′ – GAATTC – 3′
3′ – CTTAAG – 5′
(b) 5′ – CCAATG – 3′
3′ – GAATCC – 5′
(c) 5′ – CATTAG – 3′
3′ – GATAAC – 5′
(d) 5′ – GATACC – 3′
3′ – CCTAAG – 5′

Thirty percent of the bases in a sample of DNA extracted from eukaryotic cells is adenine. What percentage of cytosine is present in this DNA?
[2015]
(a) 10% (b) 20%
(c) 30% (d) 40%

There are three genes a, b, c. Percentage of crossing over between a and b is 20%, b and c is 28% and a and c is 8%. What is the sequence of genes on chromosome? [2015]
(a) b, a, c (b) a, b, c
(c) a, c, b (d) None of these

Which one of the following group of codons is called as degenerate codons? [2016]
(a) UAA, UAG and UGA
(b) GUA, GUG, GCA, GCG and GAA
(c) UUC, UUG, CCU, CAA and CUG
(d) UUA, UUG, CUU, CUC, CUA and CUG

The given figure shows the structure of nucleosome with their parts labelled as A, B & C. Identify A, B and C. [2017]

(a) A – DNA; B – H1 histone;
C – Histone octamer
(b) A – H1 histone; B – DNA;
C – Histone octamer
(c) A – Histone octamer; B – RNA;
C – H1 histone
(d) A – RNA; B – H1 histone;
C – Histone octamer

Match the codons given incolumn I with their respective amino acids given in column II and choose the correct answer. [2017]

(a) A – III; B – IV; C – I; D – V; E – II
(b) A – III; B – I; C – IV; D – V; E – II
(c) A – III; B – IV; C – V; D – I; E – II
(d) A – II; B – IV; C – I; D – V; E – III

ASSERTION REASON QUESTIONS

Directions for (Qs. 1-4) : These questions consist of two statements, each printed as Assertion and Reason. While answering these questions, you are
required to choose any one of the following five responses.
(a) If both Assertion and Reason are correct and
the Reason is a correct explanation of the Assertion.
(b) If both Assertion and Reason are correct but Reason is not a correct explanation of the Assertion.
(c) If the Assertion is correct but Reason is incorrect.
(d) If both the Assertion and Reason are incorrect.
(e) If the Assertion is incorrect but the Reason is correct.

1-Assertion : Histones are basic proteins of major importance in packaging of eukaryotic DNA. DNA and histones comprise chromatin forming
the bulk of eukaryotic chromosome.
Reason : Histones are of five major types H1,H2 H3,H3 and H4 . [2000]

2-Assertion: mRNA attaches to ribosome through its 3′ end.
Reason: The mRNA has F-capsular nucleotide and bases of lagging sequence. [2002]

3-Assertion: An organism with lethal mutation may not even develop beyond the zygote. [2006]
Reason: All types of gene mutations are lethal.

4-Assertion: Polytene chromosomes have a high amount of DNA.
Reason: Polytene chromosomes are formed by repeated replication. [2006]

Directions for (Qs.31-35) : Each of these questions contains an Assertion followed by Reason. Read them carefully and answer the question on the basis of following options. You have to select the one that best describes the two statements.
(a) If both Assertion and Reason are correct and Reason is the correct explanation of Assertion.
(b) If both Assertion and Reason are correct, but Reason is not the correct explanation of Assertion.
(c) If Assertion is correct but Reason is incorrect.
(d) If both the Assertion and Reason are incorrect

1-Assertion : DNA is associated with proteins. Reason : DNA binds around histone proteins that form a pool and the entire structure is called
a nucleosome. [2013]

2-Assertion : The uptake of DNA during transformation is an active, energy requiring process.
Reason : Transformation occurs in only those bacteria, which possess the enzymatic machinery involved in the active uptake and recombination [2014]

3-Assertion : UAA, UAG and UGA terminate protein synthesis.
Reason : They are not recognised by tRNA. [2011, 2014]

4-Assertion : In a DNA molecule, A–T rich parts melt before G–C rich parts.
Reason : In between A and T there are three H–bond, whereas in between G and C there are two H-bonds. [2010, 2015]

5-Assertion : Replication and transcription occur in the nucleus but translation takes place in the cytoplasm.
Reason : mRNA is transferred from the nucleus into cytoplasm where ribosomes and amino acids are available for protein synthesis.
[2008, 2015, 2017]

CHAPTER-29: Evolution

MULTIPLE CHOICE QUESTIONS

The branch of science dealing with process of improvement of human race by selective breeding is called [1997]
(a) Eugenics (b) Euthenics
(c) Euphenics (d) Obstetrics

The connecting link between annelida and mollusca is [1998]
(a) Neoplina (b) Nautilus
(c) Glochidium (d) Velliger larva

Theory of Pangenesis was given by [1998]
(a) Lamarck (b) Oparin
(c) Darwin (d) De Vries

The cranial capacity was largest among the [2002]
(a) Peking man (b) African man
(c) Java Ape man (d) Neanderthal man

A baby has been born with a small tail. It is the case exhibiting [2004]
(a) retrogressive evolution
(b) mutation
(c) atavism
(d) metamorphosis

The study of homologous structures in mature organisms provides evidence for the evolutionary relationships among certain groups of organisms. Which field of study includes this evidence of evolution? [2009]
(a) Comparative cytology
(b) Biochemistry
(c) Geology
(d) Comparative anatomy

Darwin’s finches were a good example of [2009]
(a) convergent evolution
(b) adaptive radiation
(c) mutation
(d) none of the above

Wings of pigeon, mosquito and bat show [1999, 2007, 2011]
(a) divergent evolution
(b) atavism
(c) convergent evolution
(d) all of these

Which of the following cannot be explained by Lamarckism? [2012]
(a) Absence of lips in snakes
(b) Long neck of giraffe
(c) Degeneration of visual apparatus in cave dwellers
(d) Dull progeny of noble laureate

Thorn of Bougainvillea and tendril of Cucurbita are example of [2013]
(a) analogous organs
(b) homologous organs
(c) vestigial organs
(d) retrogressive evolution

Forelimbs of cat, lizard used in walking; forelimbs of whale used in swimming and forelimbs of bats used in flying are an example of [2014]
(a) Analogous organs
(b) Adaptive radiation
(c) Homologous organs
(d) Convergent evolution

The diagram represents Miller’s experiment. Choose the correct combination of labelling. [2015]

(a) A–electrodes, B– NH3 + H2 + H2O + CH4,
C–cold water, D–vacuum, E–U trap
(b) A–electrodes, B–NH4 + H2 + CO2 + CH3,
C–hot water, D–vacuum, E–U trap
(c) A–electrodes, B–NH3 + H2O, C–hot water,
D–tap, E–U trap
(d) A–electrodes, B–NH3 + H2 + H2O + CH4,
C–steam, D– vacuum, E–U trap

A population is in Hardy- weinberg equilibrium for a gene with only two alleles. If the gene frequency of an allele A is 0.7, the genotype frequency of Aa is [2014, 2016]
(a) 0.21 (b) 0.42
(c) 0.36 (d) 0.7

According to Hardy-Weinberg principle, allele and genotype frequencies in a population will remain constant from generation to generation
in the absence of other evolutionary influences. It makes several assumptions which were given below. [2017]
i. Random Mating
ii. Sexual Reproduction
iii. Non-overlapping Generations
iv. Occurrence of Natural Selection
v. Small size of population
Identify two assumptions which do not meet for a population to reach Hardy-Weinberg Equilibrium?
(a) iv and v (b) ii and iv
(c) iii, iv and v (d) i, ii and iii

Which of the following was most similar to modern man? [2017]
(a) Java man
(b) Neanderthal man
(c) Homo habilis
(d) Cro-Magnon man

ASSERTION REASON QUESTIONS

Directions for (Qs. 1-10) : These questions consist of two statements, each printed as Assertion and Reason. While answering these questions, you are
required to choose any one of the following five responses.
(a) If both Assertion and Reason are correct and the Reason is a correct explanation of the Assertion.
(b) If both Assertion and Reason are correct but Reason is not a correct explanation of the Assertion.
(c) If the Assertion is correct but Reason is incorrect.
(d) If both the Assertion and Reason are incorrect.
(e) If the Assertion is incorrect but the Reason is correct.

1-Assertion: We have lost all the direct evidence of origin of life.
Reason: The persons responsible for protecting evidences were not skilled. [1998]

2-Assertion : Ginkgo biloba is a living fossil.
Reason : Organism which have persisted and remain unchanged for the past several million years while their relatives disappeared. [2000]

3-Assertion : Among the primates, chimpanzee is the closest relative of the present day humans.
Reason : The banding pattern in the autosome numbers 3 and 6 of man and chimpanzee is remarkably similar. [2004]

4-Assertion : From evolutionary point of view, human gestation period is believed to be shortening.
Reason : One major evolutionary trend in humans has been the larger head undergoing relatively faster growth rate in the foetal stage. [2004]

5-Assertion : Coacervates are believed to be the precursors of life.
Reason : Coacervates were self-duplicating aggregates of proteins surrounded by lipid molecules. [2004]

6-Assertion : Human ancestors never used their tails and so the tail expressing gene has disappeared in them.
Reason : Lamarck’s theory of evolution is popularly called theory of continuity of germ plasm. [2005]

7-Assertion : Comparative biochemistry provides a strong evidence in favour of common ancestory of living beings.
Reason : Genetic code is universal. [2005]

8-Assertion : Darwin’s finches show a variety of beaks suited for eating large seeds, flying insects and cactus seeds.
Reason : Ancestral seed-eating stock of Darwin’s finches radiated out from South American mainland to different geographical areas of the Galapagos Islands, where they found competitor-free new habitats. [2005]

9-Assertion : The earliest organisms that appeared on the earth were non-green and presumably anaerobes.
Reason :The first autotrophic organisms were the chemoautotrophs that never released oxygen. [2006]

10-Assertion : The earliest fossil form in the phylogeny of horse is eohippus.
Reason : Eohippus lived during the early pliocene epoch. [2007]

Directions for (Qs.27-30) : Each of these questions contains an Assertion followed by Reason. Read them carefully and answer the question on the basis of following options. You have to select the one that best describes the two statements.
(a) If both Assertion and Reason are correct and Reason is the correct explanation of Assertion.
(b) If both Assertion and Reason are correct, but Reason is not the correct explanation of Assertion.
(c) If Assertion is correct but Reason is incorrect.
(d) If both the Assertion and Reason are incorrect.

1-Assertion : The primitive atmosphere was reducing one i.e., without oxygen. [2009]
Reason : In the primitive atmosphere, oxygen was involved in forming ozone.

2-Assertion : Jave Ape-man, Peking man and Heidelberg man are the fossils of Homo erectus.
Reason : Homo erectus evolved from Homo habilis. [2009]

3-Assertion : Natural selection is the outcome of difference in survival and reproduction among individuals that show variation in one or more
traits.
Reason : Adaptive forms of a given trait tend to become more common; less adaptive ones become less common or disappear. [2004, 2012]

4-Assertion : Organic compounds first evolved in earth required for origin of life were protein and nucleic acid.
Reason : All life forms were in water environment only. [2016]

CHAPTER-30: Human Health & Diseases

MULTIPLE CHOICE QUESTIONS

MULTIPLE CHOICE QUESTIONS

Gambusia fish has been introduced in lakes and ponds of India to control a deadly disease. It feeds on larva of [1997]
(a) nepenthes (b) anopheles
(c) dragon fly (d) house-fly

Anti-viral substance is [1997]
(a) antigen (b) antibody
(c) interferon (d) antibiotic

Which malarial parasite has longest incubation period? [1997]
(a) Plasmodium vivax
(b) Plasmodium falciparum
(c) Plasmodium malariae
(d) Plasmodium ovale

The type of antibodies present in colostrum secreted from mammary gland is [1997]
(a) IgM (b) IgD
(c) IgE (d) IgA

Which of the following disease is due to an allergic reaction ? [1998]
(a) Goitre (b) Hay fever
(c) Skin cancer (d) Rheumatic fever

Influenza is caused by [1998]
(a) virus (b) bacteria
(c) alga (d) fungus

Which type of cancer is found in lymph nodes and spleen? [1998]
(a) Carcinoma (b) Sarcoma
(c) Lymphoma (d) Leukemia

Amoebiasis is caused by [1999]
(a) Entamoeba histolytica
(b) Taenia solium
(c) Plasmodium vivax
(d) E. coli

Inflammatory response, in allergy is caused by the release of [1999]
(a) antigen (b) histones
(c) histamines (d) antibodies

Sporogony of malarial parasite occurs in [1999]
(a) liver of man
(b) RBCs of man
(c) stomach wall of mosquito
(d) salivary glands of mosquito

Malignant tertain malaria is caused by [2000]
(a) P. vivax (b) P. malariae
(c) P. ovale (d) P. falciparum

HIV has a protein coat and genetic material [2000]
(a) ss RNA (b) ds RNA
(c) ss DNA (d) ds DNA

Cyclosporine is used [2002]
(a) For allergy
(b) As immunodepressent
(c) Prophylactic for virus
(d) None of the above

Lysis of foreign cell is mediated through [2002]
(a) IgM (b) IgA
(c) IgE (d) IgM & IgG

The treatment of snake-bite by antivenom is an example of [2004]
(a) artificially acquired active immunity
(b) artificially acquired passive immunity
(c) naturally acquired passive immunity
(d) specific natural immunity

Electron beam therapy is a kind of radiation therapy to treat [2004]
(a) enlarged prostate gland
(b) gall bladder stones by breaking them
(c) certain types of cancer
(d) kidney stones

A young drug addict used to show symptoms of depressed brain activity, feeling of calmness, relaxation and drowsiness. Possibly he was taking [2005]
(a) Amphetamine (b) Marijuana
(c) Pethadine (d) Valium

When children play bare footed in pools of dirty water and flood water, they may suffer from diseases like [2006]
(a) leptospirosis and bilharizia
(b) malaria, amoebic dysentery and leptospirosis
(c) bilharizia, infective hepatitis and diarrhoea
(d) guinea worm infection, elephantiasis and amoebic dysentery

Which one of the following is not a matching pair of a drug and its category ? [2004, 2008]
(a) Amphetamines – stimulant
(b) Lysergic acid – narcotic dimethyl amide
(c) Heroin – psychotropic
(d) Benzodiazepam – pain killer

An insect bite may result in inflammation of that spot. This is triggered by the alarm chemicals such as [2005, 2008]
(a) histamine and dopamine
(b) histamine and kinins
(c) interferons and opsonin
(d) interferons and histones

Antigen binding site in an antibody is found between [2005, 2008]
(a) two light chains
(b) two heavy chains
(c) one heavy and one light chain
(d) either between two light chains or between one heavy and one light chain depending upon the nature of antigen

The antigen-binding site are present where on the antibody molecule [2009]
(a) on light chain as well as on heavy chain.
(b) on light chain only.
(c) on variable region and constant region of light chain.
(d) on heavy chain only

Which one of the following antimicrobial drugs is suitable for treatment of both tuberculosis and leprosy? [2010]
(a) Isoniazid
(b) R-aminosalicylic acid
(c) Streptomycin
(d) Rifampicin

Antigen is a substance which [2010]
(a) lowers body temperature
(b) destroys harmful bacteria
(c) triggers the immune system
(d) is used as an antidote to poison

Which of the following is a pentameric immunoglobulin and is produced first in a primary response to an antigen? [2010]
(a) Ig G (b) Ig M
(c) IgA (d) Ig E

Cattle fed with spoilt hay to sweet clover which contains dicumarol [2011]
(a) are healthier due to a good diet
(b) catch infections easily
(c) may suffer vitamin K deficiency and prolonged bleeding
(d) may suffer from beri-beri due to deficiency of vitamin-B

Opium is obtained from [2011]
(a) Oryza sativa
(b) Coffea arabica
(c) Thea sinensis
(d) Papaver somniferum

Match the following bacteria with the diseases
Column-I_____________________ Column-II
A. Treponema pallidum …………I. Plague
B. Yersinia pestis ……………………II. Anthrax
C. Bacillus anthracis……………… III. Syphilis
D. Vibrio…………………………………. IV. Cholera
[2012]
(a) A – III; B – I; C – II; D – IV
(b) A – IV; B – I; C – II; D – III
(c) A – III; B – II; C – I; D – IV
(d) A – I; B – III; C – II; D – IV

Which one of the following is a correct match?
[2013]
(a) Bhang – Analgesic
(b) Cocaine – Opiate narcotics
(c) Morphine – Hallucinogen
(d) Barbiturate – Tranquiliser

Which of the following is an autoimmune disorder? [2013]
(a) Myasthenia gravis
(b) Osteoporosis
(c) Muscular dystrophy
(d) Gout

Which of the following is based upon the principle of antigen-antibody interaction? [2014]
(a) PCR
(b) ELISA
(c) r-DNA technology
(d) RNA

Identify the molecules (A) and (B) shown below and select the right option giving their source and use.

Which of the following pairs is not correctly matched ? [2016]
(a) Cholera – Vibrio cholerae
(b) German measles – Rubella virus
(c) Whooping cough – Bordetella pertussis
(d) Tetanus – Pasteurella pestis

Human immuno deficiency virus (HIV) has a protein coat and a genetic material which is [2017]
(a) Single stranded DNA.
(b) Single stranded RNA.
(c) Double stranded RNA.
(d) Double stranded DNA.

Which one of the following pairs of diseases is viral as well as transmitted by mosquitoes? [2017]
(a) Elephantiasis and dengue
(b) Yellow fever and sleeping sickness
(c) Encephalitis and sleeping sickness
(d) Yellow fever and dengue

ASSERTION REASON QUESTIONS

Directions for (Qs. 1-8) : These questions consist of two statements, each printed as Assertion and Reason. While answering these questions, you are
required to choose any one of the following five responses.
(a) If both Assertion and Reason are correct and the Reason is a correct explanation of the Assertion.
(b) If both Assertion and Reason are correct but Reason is not a correct explanation of the Assertion.
(c) If the Assertion is correct but Reason is incorrect.
(d) If both the Assertion and Reason are incorrect.
(e) If the Assertion is incorrect but the Reason is correct.

1-Assertion: There is no chance of malaria to a man on the bite of male Anopheles mosquito.
Reason: It carries a non-virulant strain of Plasmodium.

2-Assertion : Rabies is an infection of mammals, it involves central nervous system which may
result in paralysis and finally death.
Reason : This is caused by neurotropic bacteria
in saliva of rabies animal. [2000]

3-Assertion : Plasmodium vivax is responsible for malaria.
Reason : Malaria is caused by polluted water. [2001]

4-Assertion: Histamine is related with allergic and inflammatory reactions.
Reason: Histamine is a vasodilator. [2002]

5-Assertion : Organ transplantation patients are given immunosuppressive drugs.
Reason : Transplanted tissue has antigens which stimulate the specific immune response of the recipient. [2005]

6-Assertion: LSD and marijuana are clinically used as a analgesics. [2006]
Reason:Both these drugs suppress brain function.

7-Assertion : A person who has received a cut and is bleeding needs to be given anti-tetanus treatment. [2006]
Reason : Anti-tetanus injection provides immunity by producing antibodies for tetanus.

8-Assertion (A) : Antigen can be easily recognized because it has antigenic determinants.
Reason (R) : The recognition ability is innate. [2007]

Directions for (Qs.1-12) : Each of these questions contains an Assertion followed by Reason. Read them carefully and answer the question on the basis of following options. You have to select the one that best describes the two statements.
(a) If both Assertion and Reason are correct and Reason is the correct explanation of Assertion.
(b) If both Assertion and Reason are correct, but Reason is not the correct explanation of Assertion.
(c) If Assertion is correct but Reason is incorrect.
(d) If both the Assertion and Reason are incorrect.

1-Assertion : Escherichia coli, Shigella sp. and Salmonella sp. are all responsible for diarrhoeal diseases.
Reason : Dehydration is common to all types of diarrhoeal diseases and adequate supply of fluids and electrolytes should be ensured.
[2008]

2-Assertion : Dope test is used to estimate the level of blood alcohol by analyzing the breath of persons drinking alcohol.
Reason : A drunken person usually feels tense and less talkative. [2004, 2008]

3-Assertion : Interferons are a type of’antibodies produced by body cells infected by bacteria.
Reason : Interferons stimulate inflammation at the site of injury. [2004, 2008]

4-Assertion : Mast cells in the human body release excessive amounts of inflammatory chemicals, which cause allergic reactions.
Reason : Allergens in the environment on reaching human body stimulate mast cells in certain individuals. [2003, 2008]

5-Assertion : Cannabis sativa is a powerful anti-depressant.
Reason : Hashish and Marijuana are derived from it. [2009]

6-Assertion: Epstein– Barr virus is an oncovirus.
Reason: It stimulates the growth of cancer.[2011]

7-Assertion: HIV infected person are prone to oppurtunistic diseases.
Reason: Immune system weakens during HIV infection. [2011]

8-Assertion : Histamine is involved in allergic and inflammatory reactions.
Reason : Histamine is a vasodilator. [2012]

8-Assertion : The antibodies separted from serum are homogenous.
Reason : Monoclonal antibodies are homogenous immunological reagents. [2013]

9-Assertion : Interferons are effective against viruses.
Reason : Proteins which can be synthesized only by genetic engineering are effective against viruses. [2013, 2014]

10-Assertion : Cancer cells are virtually immortal until the body in which they reside dies.
Reason : Cancer is caused by damage to genes regulating the cell division cycle. [2006, 2015]

11-Assertion : Cocaine has a potent stimulating action on central nervous system, producing a sense of euphoria and increased energy.
Reason : Injecting the microbes intentionally during immunisation or infectious organisms gaining access into body during natural infection
induces active immunity. [2016]

12-Assertion: Artificially acquired passive immunity results when antibodies or lymphocytes produced outside the host are introduced into a host.
Reason: A bone marrow transplant given to a patient with genetic immunodeficiency is an example of artificially acquired passive immunity.
[2017]

CHAPTER-31: Strategies for Enhancement in Food Production

MULTIPLE CHOICE QUESTIONS

The chemical which are produced by host plants due to infection as a defence reaction to pathogen, are called [1997]
(a) phytotoxin (b) toxin
(c) phytotron (d) phytoalexins

Auxanometer is used to measure [1998]
(a) length (b) respiration
(c) transpiration (d) ascent of sap

Crop rotation is used to increase [1999]
(a) soil fertility
(b) pore size and soil particle
(c) organic content of soil
(d) viscosity of soil water

Haploid cultures can be obtained by culturing
(a) pollen grains (b) embryo [2000]
(c) shoot apex (d) root apex

Azolla is used as a biofertilizer because it[2003]
(a) multiplies very fast to produce massive biomass
(b) has association of nitrogen-fixing Rhizobium
(c) has association of nitrogen-fixing Cyanobacteria
(d) has association of mycorrhiza

Pruning of plants promotes branching because the axillary buds get sensitized to [2004]
(a) ethylene (b) gibberellin
(c) cytokinin (d) indole acetic acid

Somaclonal variation can be obtained by[2004]
(a) application of colchicine
(b) irradiation with gamma rays
(c) tissue culture
(d) hybridisation

Somaclonal variation appears in [2005]
(a) organisms produced through somatic hybridization.
(b) plants growing in highly polluted conditions.
(c) apomictic plants.
(d) tissue culture raised plants.

In an experiment freshly hatched larvae of an insect (Khapra beetle) were reared on a basal diet (complete diet without cholesterol) with increasing amounts of cholesterol. Results obtained are shown in the given graph.
[2005, 2008]

The graph indicates
(a) cholesterol is an essential dietary requirement of khapra beetle.
(b) growth of khapra beetle is directly proportional to cholesterol concentration.
(c) cholesterol concentration of 2 μg/g diet is the optimum level.
(d) growth of khapra beetle is inhibited when cholesterol concentration exceeds 5 μg/g diet.

A scion is grafted to a stock. The quality of fruits produced will be determined by the genotype of [2006]
(a) stock
(b) scion
(c) both stock and scion
(d) neither stock nor scion

Cocoa is the plant from which chocolate is made. Which part is used to extract it? [2007]
(a) Flower (b) Fruit
(c) Seeds (d) Bark

Bean seeds were planted and put on a sunny windowsill. As the plants grew, their stems bent toward the window. This bending was most likely
caused by an [2009]
Strategies for Enhancement in
(a) unequal distribution of auxin in the stem.
(b) unequal distribution of a neurotransmitter in the stem.
(c) equal distribution of auxin in the stem.
(d) equal distribution of a neurotransmitter in the stem.

Phytotron is a facility to [2010]
(a) grow plants under disease-free conditions.
(b) conserve endangered species of plants.
(c) grow plants under controlled conditions.
(d) induce mutations

Essential oils are those which [2011]
(a) are essential to the plant itself
(b) are used as lubricants
(c) produce perfumes
(d) are essential for human beings

Coconut water is rich in [2011]
(a) auxins (b) gibberellins
(c) abscisic acid (d) cytokinin

Which of the following is the pair of biofertilizers? [2014]
(a) Azolla and BGA
(b) Nostoc and legume
(c) Rhizobium and grasses
(d) Salmonella & E. coli

Hisardale is a new breed of sheep developed in Punjab by one of the breeding technique in which superior male of one breed is mated with
superior females of another breed. Identify the breeding technique from the option given below. [2016]
(a) Inbreeding (b) Out crossing
(c) Out breeding (d) Cross breeding

Biodiversity loss occurs due to the reasons given below. [2017]
(i) Habitat loss and fragmentation
(ii) Co-extinction
(iii) Over-exploitation
(iv) Alien species invasion
Identify the correct reasons.
(a) (i) and (ii) (b) (i), (ii) and (iii)
(c) (ii), (iii) and (iv) (d) (i), (ii), (iii) and (iv)

Explant is required to be disinfected before placing in culture. This is done by [2017]
(a) autoclaving
(b) ultra-violet rays
(c) clorax or hypochlorite
(d) X-rays

Which of the following is a viral disease of poultry birds? [2017]
(a) Anthrax (b) Ranikhet
(c) Coccidiosis (d) None of these

ASSERTION REASON QUESTIONS

Directions for (Qs. 1-5) : These questions consist of two statements, each printed as Assertion and Reason. While answering these questions, you are
required to choose any one of the following five responses.
(a) If both Assertion and Reason are correct and the Reason is a correct explanation of the Assertion.
(b) If both Assertion and Reason are correct but Reason is not a correct explanation of the Assertion.
(c) If the Assertion is correct but Reason is incorrect.
(d) If both the Assertion and Reason are incorrect.
(e) If the Assertion is incorrect but the Reason is correct.

1-Assertion : In plant tissue culture somatic embryos can be induced from any plant cell.
Reason : Any viable plant cell can differentiate into somatic embryos. [2003]

2-Assertion : Use of fertilizers greatly enhances crop productivity.
Reason : Irrigation is very important in increasing crop productivity. [2003]

3-Assertion : Fish meal is a rich source of protein for cattle and poultry.
Reason : Fish meal is produced from non-edible parts of fishes like fins, tail etc. [2004]

4-Assertion : Cattle breeds can be improved by super ovulation and embryo transplantation.
Reason : Superovulation in high milk-yielding cows is induced by hormonal injection. [2004]

5-Assertion (A) : Vernalization is acceleration of subsequent flowering by low temperature treatment.
Reason (R) : Site of vernalization is apical meristem. [2007]

Directions for (Qs. 26-31) : Each of these questions contains an Assertion followed by Reason. Read them carefully and answer the question on the basis of following options. You have to select the one that best describes the two statements.
(a) If both Assertion and Reason are correct and Reason is the correct explanation of Assertion.
(b) If both Assertion and Reason are correct, but Reason is not the correct explanation of Assertion.
(c) If Assertion is correct but Reason is incorrect.
(d) If both the Assertion and Reason are incorrect.

1-Assertion : In plant tissue culture, somatic embryos can be induced from any plant cell.
Reason : Any viable plant cell can differentiate into somatic embryos. [2008]

2-Assertion : Cattle breeds can be improved by superovulaton and embryo transplantaion.
Reason : Superovulation in high milk-yielding cows is induced by hormonal injection. [2013]

3-Assertion : In case of vegetatively propagated crops, pure-line selection is not required.
Reason : Hybrid vigour is mostly used in vegetatively propagated plants. [2013]

4-Assertion : Yeasts such as Saccharomyces cerevisiae are used in baking industry.
Reason : Carbon dioxide produced during fermentation causes bread dough to rise by thermal expansion. [2015]

5-Assertion : Somatic embryos can be induced from any cell in plant tissue culture.
Reason : Any living plant cell is capable of differentiating into somatic embryos. [2017]

6-Assertion : A major advantage of tissue culture is protoplast fusion.
Reason : A hybrid is formed by the fusion of naked protoplasts of two plants. [2017]

chapter-32: Microbes in Human Welfare

MULTIPLE CHOICE QUESTIONS

Which of the following antibiotic was discovered by Alexander Flemming ? [2000]
(a) Streptomycin (b) Tetracycline
(c) Penicillin (d) Terramycin

Which one of the following pairs is correctly matched? [2003]
(a) Rhizobium – Parasite in the roots of leguminous plants.
(b) Mycorrhizae – Mineral uptake from soil.
(c) Yeast – Production of biogas.
(d) Myxomycetes – The ringworm diseases.

The bacteria Pseudomonas is useful because of its ability to [2004]
(a) transfer genes from one plant to another.
(b) decompose a variety of organic compounds.
(c) fix atmospheric nitrogen in the soil.
(d) produce a wide variety of antibiotics.

Chloramphenicol and erythromycin (broad spectrum antibiotics) are produced by [2014]
(a) Streptomyces (b) Nitrobacter
(c) Rhizobium (d) Penicillium

A patient brought to a hospital with myocardial infarction is normally immediately given: [2014]
(a) Penicillin (b) Streptokinase
(c) Cyclosporin-A (d) Statins

Microbes are used in [2015]

  1. primary treatment of sewage
  2. secondary treatment of sewage
  3. anaerobic sludge digester
  4. production of bioactive molecules
    (a) 1, 3 and 4 (b) 1, 2, 3 and 4
    (c) 2, 3 and 4 (d) 3 and 4

Choose the right combination
Column-I ________________Column-II
A. Escherichia coli ………….I. Nif gene
B. Rhizobium melilotae ….II. Digestive
hydrocarbon
of crude oil

C. Bacillus thuringiensis ………..III. Production of
human insulin
D. Pseudomonas putida…………. IV. Biological
control of fungal disease
V. Biodecomposed
insectiside [2016]

(a) A – III; B – I; C – V; D – IV
(b) A – I; B – II; C – III; D – IV
(c) A – II; B – I; C – III; D – IV
(d) A – III; B – I; C – V; D – II

What would happen if oxygen availability to activated sludge flocs is reduced? [2016]
(a) It will slow down the rate of degradation of organic matter.
(b) The centre of flocs will become anoxic, which would cause death of bacteria and eventually breakage of flocs.
(c) Flocs would increase in size as anaerobic bacteria would grow around flocs.
(d) Protozoa would grow in large numbers.

Which one of the following statement regarding BOD is true? [2017]
(a) The greater the BOD of waste water, more is its polluting potential.
(b) The greater the BOD of waste water, less is its polluting potential.
(c) The lesser the BOD of waste water, more is its polluting potential.
(d) The lesser the BOD of waste water, less is its polluting potential.

The free-living fungus Trichoderma can be used for [2017]
(a) killing insects
(b) biological control of plant diseases
(c) controlling butterfly caterpillars
(d) producing antibiotics

ASSERTION REASON QUESTIONS

Directions for (Qs. 1-2) : These questions consist of two statements, each printed as Assertion and Reason. While answering these questions, you are
required to choose any one of the following five responses.
(a) If both Assertion and Reason are correct and the Reason is a correct explanation of the Assertion.
(b) If both Assertion and Reason are correct but Reason is not a correct explanation of the Assertion.
(c) If the Assertion is correct but Reason is incorrect.
(d) If both the Assertion and Reason are incorrect.
(e) If the Assertion is incorrect but the Reason is correct.

1-Assertion : Leguminous plants are nitrogen fixers.
Reason : Leguminous plants have Rhizobium in their root nodules. [1997]

2-Assertion : Nitrogen-fixing enzyme in legume root nodules function at low oxygen concentration.
Reason : Low oxygen concentration is provided by leghaemoglobin. [2004]

Directions for (Qs.1-3) : Each of these questions contains an Assertion followed by Reason. Read them carefully and answer the question on the basis of following options. You have to select the one that best describes the two statements.
(a) If both Assertion and Reason are correct and Reason is the correct explanation of Assertion.
(b) If both Assertion and Reason are correct, but Reason is not the correct explanation of Assertion.
(c) If Assertion is correct but Reason is incorrect.
(d) If both the Assertion and Reason are incorrect

1-Assertion : Lichen is important for chemical industries.
Reason : Litmus and Orcein are formed from lichens. [2009]

2-Assertion : Yeasts such as Saccharomyces cerevisiae are used in baking industry [2003, 2011]
Reason : Carbon dioxide produced during fermentation causes bread dough to rise by thermal expansion.

3-Assertion : Vitamins B2 is found in cereals, green vegetables, brewer’s yeast, egg white, milk and liver.
Reason : It can be commercially produced by some yeasts. [2014]

CHAPTER-33: Biotechnology: Principles and Processes

MULTIPLE CHOICE QUESTIONS

Restriction endonucleases are used as [1998]
(a) molecular build up at nucleotides.
(b) molecular degradation to DNA breakup.
(c) molecular knives for cutting DNA at specific sites.
(d) molecular cement to combine DNA sites.

In genetic engineering, which of the following is used ? [2001]
(a) Plasmid (b) Plastid
(c) Mitochondria (d) E.R.

Introduction of foreign gene for improving genotype is called [2002]
(a) tissue culture
(b) vernalization
(c) genetic engineering
(d) eugenics

An example of gene therapy is [2004]
(a) production of injectable hepatitis B vaccine.
(b) production of vaccines in food crops like potatoes which can be eaten.
(c) introduction of gene for adenosine deaminase in persons suffering from Severe Combined Immuno Deficiency (SCID).
(d) production of test tube babies by artificial insemination and implantation of fertilized eggs.

c-DNA probes are copied from the messenger RNA molecules with the help of [2005]
(a) restriction enzymes
(b) reverse transcriptase
(c) DNA polyermase
(d) adenosine deaminase

Electroporation procedure involves [2005]
(a) fast passage of food through sieve pores in phloem elements with the help of electric stimulation.
(b) opening of stomatal pores during night by artificial light.
(c) making transient pores in the cell membrane to introduce gene constructs.
(d) purification of saline water with the help of a membrane system.

What is the first step in the Southern blot technique? [2004, 2008]
(a) Denaturation of DNA on the gel for hybridization with specific probe.
(b) Production of a group of genetically identical cells.
(c) Digestion of DNA by restriction enzyme.
(d) Denaturation of DNA from a nucleated cell such as the one from the scene of crime.

The polymerase chain reaction (PCR) technology was discovered by [2009]
(a) Karry Mullis
(b) Saiki et al
(c) Craig Venter
(d) Maxam and Gilbert

After 4 PCR cycles how many DNA molecules are formed from one DNA template molecule ?[2012]
(a) 4 (b) 32
(c) 16 (d) 8

Human Genome Project (HGP) is closely associated with the rapid development of a new area in biology called as [2013]
(a) biotechnology (b) bioinformatics
(c) biogeography (d) bioscience

Identify the correct match for the given apparatus. [2013]

Apparatus ___________Function
(a) Gene gun …………….Vectorless direct gene transfer
(b) Column………………..Separation of chlorophyll pigments
chromatograph
(c) Stirred tank………….. Carry out fermentation process
bioreactor
(d) Respirometer ………..Finding out rate of respiration

Genes of interest can be selected from a genomic library by using [2014]
(a) Restriction enzymes
(b) Cloning vectors
(c) DNA probes
(d) Gene targets

Choose the correct option.

Which one of the following palindromic base sequences in DNA can be easily cut at about the middle by some particular restriction enzyme? [2016]
(a) 5’………….CGTTCG………….3′
3’………….ATGGTA………….5′
(b) 5’………….GATATG………….3′
3’………….CTACTA………….5′
(c) 5’………….GAATTC………….3′
3’………….CTTAAG………….5′
(d) 5’………….CACGTA………….3′
3’………….CTCAGT………….5′

Which of the following statement is not correct about cloning vector ? [2017]
(a) ‘Ori’ is a sequence responsible for controlling the copy number of the linked DNA.
(b) Selectable marker selectively permitting the growth of the non-transformants.
(c) In order to link the alien DNA, the vector needs to have single recognition site for the commonly used restriction enzymes.
(d) The ligation of alien DNA is carried out at a restriction site present in one of the two antibiotic resistance genes.

ASSERTION REASON QUESTIONS

Directions for (Qs. 1-5) : These questions consist of two statements, each printed as Assertion and Reason. While answering these questions, you are
required to choose any one of the following five responses.
(a) If both Assertion and Reason are correct and the Reason is a correct explanation of the Assertion.
(b) If both Assertion and Reason are correct but Reason is not a correct explanation of the Assertion.
(c) If the Assertion is correct but Reason is incorrect.
(d) If both the Assertion and Reason are incorrect.
(e) If the Assertion is incorrect but the Reason is correct.

1-Assertion : Plasmids are extrachromosomal DNA.
Reason : Plasmids are found in bacteria and are useful in genetic engineering. [2001]

2-Assertion: Plasmids are single-stranded extra chromosomal DNA.
Reason: Plasmids are usually present in eukaryotic cells.

3-Assertion: Clones are produced by sexual reproduction.
Reason: These are prepared by group of cells descended from many cells or by inbreeding of a heterozygous line.

4-Assertion : In recombinant DNA technology human genes are often transferred into bacteria (prokaryotes) or yeast (eukaryote).
Reason : Both bacteria and yeast multiply very fast to form huge population which expresses the desired gene. [2005]

5-Assertion : Agrobacterium tumefaciens is popular in genetic engineering because this bacterium is associated with the roots of all cereal and pulse crops.
Reason : A gene incorporated in the bacterial chromosomal genome-gets automatically transferred to the crop with which the bacterium
is associated. [2005]

Directions for (Qs. 1-4) : Each of these questions contains an Assertion followed by Reason. Read them carefully and answer the question on the basis of following options. You have to select the one that best describes the two statements.
(a) If both Assertion and Reason are correct and Reason is the correct explanation of Assertion.
(b) If both Assertion and Reason are correct, but Reason is not the correct explanation of Assertion.
(c) If Assertion is correct but Reason is incorrect.
(d) If both the Assertion and Reason are incorrect.

1-Assertion : Restriction enzymes cut the strand of DNA to produce sticky ends. [2009]
Reason : Stickiness of the ends facilitates the action of the enzyme DNA polymerase.

2-Assertion : “DNA finger printing” has become a powerful tool to establish paternity and identity of criminals in rape and assault cases. [2010]
Reason : Trace evidences such as hairs, saliva and dried semen are adequate for DNA analysis.

3-Assertion : In recombinant DNA technology, human genes are often transferred into bacteria (prokaryotes) or yeast (eukaryote). .
Reason : Both bacteria and yeast multiply very fast to form huge population, which express the desired gene. [2008, 2015]

4-Assertion : Insertion of recombinant DNA within the coding sequence of β-galactosidase results in colourless colonies.
Reason : Presence of insert results in inactivation of enzyme β-galactosidase known as insertional inactivation. [2017]

CHAPTER-34:Biotechnology & its Applications

MULTIPLE CHOICE QUESTIONS

A tumour inducing plasmid widely used in the production of transgenic plant is that of [2005]
(a) Escherichia coli
(b) Bacillus thuringiensis
(c) Staphylococcus aureus
(d) Agrobacterium tumefaciens

Which one of the following is a correct statement? [2005]
(a) “Bt” in “Bt-cotton” indicates that it is a genetically modified organism produced through biotechnology.
(b) Somatic hybridization involves fusion of two complete plant cells carrying desired genes.
(c) The anticoagulant ‘hirudin’ is being produced from transgenic Brassica napus seeds.
(d) “Flavr Savr” variety of tomato has enhanced the production of ethylene
which improves its taste.

Cultivation of Bt cotton has been much in the news. The prefix Bt means [2008]
(a) barium-treated cotton seeds
(b) bigger thread variety of cotton with better tensile strength
(c) produced by biotechnology using restriction enzymes and ligases
(d) carrying an endotoxin gene from Bacillus thuringiensis

Golden rice is a transgenic crop of the future with the following improved trait [2012]
(a) High lysine (essential amino acid) content
(b) Insect resistance
(c) High protein content
(d) High vitamin-A content

How many varieties of rice has been estimated to be present in India? [2013]
(a) 2,000 (b) 20,000
(c) 200,000 (d) 2,000,000

The scientific process by which crop plants are enriched with certain desirable nutrients is called [2013]
(a) crop protection (b) breeding
(c) bio-fortification (d) bio-remediation

Which of the following is a variety of Brassica resistance to white rust disease? [2014]
(a) Himgiri
(b) Pusa Kamal
(c) Pusa Swarnim (Karan rai)
(d) Pusa Sadabahar

The first clinical gene therapy was given in 1990 to a 4 years old girl with enzyme deficiency of [2014]
(a) Adenosine deaminase (ADA)
(b) Tyrosine oxidase
(c) Monamine oxidase
(d) Glutamate dehydrogenase

Select the correct statement(s)- [2015]
(1) IARI has released a mustard variety rich in vitamin C.
(2) Pusa Sawani variety of Okra is resistant to aphids.
(3) Hairiness of leaves provides resistance to insect pests.
(4) Agriculture accounts for approximately 33% of India’s GDP and employs nearly 62% of the population.
(a) (1) and (2) (b) (2) and (3)
(c) (1), (3) and (4) (d) None of these

Read the following four statements (1-4) about certain mistakes in two of them

  1. The first transgenic buffalo, Rosie produced milk which was human alphalactal albumin enriched.
  2. Restriction enzymes are used in isolation of DNA from other macro-molecules.
  3. Downstream processing is one of the steps of R-DNA technology.
    34 Biotechnology & its Applications B-184 Topicwise AIIMS Solved Papers – BIOLOGY
  4. Disarmed pathogen vectors are also used in transfer of R-DNA into the host.
    Which are the two statements having mistakes? [2015]
    (a) Statement 2 and 3 (b) Statement 3 and 4
    (c) Statement 1 and 3 (d) Statement 1 and 2

A transgenic food crop which may help in solving the problem of night blindness in developing countries is [2016]
(a) golden rice (b) Bt soyabean
(c) flavr – savr tomato (d) starlink maize

Which variety of rice was patented by a U.S. company even though the highest number of varieties of this rice is found in India ? [2017]
(a) Sharbati Sonara (b) Co-667
(c) Basmati (d) Lerma Roja

Directions for (Q. 1) : Each of these questions contains an Assertion followed by Reason. Read them carefully and answer the question on the basis of following options. You have to select the one that best describes the two statements.
(a) If both Assertion and Reason are correct and Reason is the correct explanation of Assertion.
(b) If both Assertion and Reason are correct, but Reason is not the correct explanation of Assertion.
(c) If Assertion is correct but Reason is incorrect.
(d) If both the Assertion and Reason are incorrect.

1-Assertion : Insect resistant transgenic cotton has been produced by inserting Bt gene. [2010]
Reason : The Bt gene is derived from a bacterium.

CHAPTER-35:Organisms and Populations

MULTIPLE CHOICE QUESTIONS

Territoriality occurs as a result of [1998]
(a) competition (b) parasitism
(c) predation (d) co-operation

Obligate parasites live on [1999]
(a) living host only
(b) living host and dead organic matter
(c) dead organic matter only
(d) artificial liquid medium

Mycorrhiza help in absorption of [1999]
(a) calcium (b) nutrients
(c) metals (d) none of these

The plants which can withstand narrow range of temperature tolerance are called [2000]
(a) stenothermal (b) eurythermal
(c) mesothermal (d) monothermal

Abundance of a species in a population, within habitat is called [2001]
(a) niche density
(b) absolute density
(c) relative density
(d) geographic density

The maintenance of internal favourable conditions, by a self regulated mechanisms inspite of the fact that there are changes in environment, is known as [2001]
(a) entropy (b) enthalpy
(c) homoeostasis (d) steady state

July 11 is observed as [2003]
(a) World Population Day
(b) No Tobacco Day
(c) World Environment Day
(d) World Health Day

Which one of the following is a matching pair of certain organism(s) and the kind of association? [2003]
(a) Shark and sucker fish – Commensalism
(b) Algae and fungi in lichens – Mutualism
(c) Orchids growing on trees – Parasitism
(d) Cuscuta (dodder) growing on other – flowering plants – Epiphytism

The great barrier reef along the east coast of Australia can be categorised as [2004]
(a) population (b) community
(c) ecosystem (d) biome

Which one of the following correctly represents an organism and its ecological niche ? [2005]
(a) Vallisneria and pond
(b) Desert locust (Schistocerca) and desert
(c) Plant lice (aphids) and leaf
(d) Vultures and dense forest

Keystone species deserve protection because these [2006]
(a) are capable of surviving in harsh environmental conditions.
(b) indicate presence of certain minerals in the soil.
(c) have become rare due to overexploitation.
(d) play an important role in supporting other species.

A lizard-like member of reptila is sitting on a tree with its tail coiled around a twig. This animal could be [2006]
(a) Hemidactylus showing sexual dimorphism
(b) Varanus showing mimicry
(c) Garden lizard (Calotes) showing camouflage
(d) Chamaeleon showing protective colouration

Carrying capacity is [2009]
(a) the capacity of an individual to produce young ones.
(b) availability of resources in a given habitat to support a certain no of individuals of population, beyond which no further growth is possible.
(c) gene frequency from one generation to next.
(d) gene frequency in same generation.

Within biological communities, some species are important in determining the ability of a large number of other species to persist in the community. Such species are called [2010]
(a) keystone species
(b) allopatric species
(c) sympatric species
(d) threatened species

Presence of flagellated protozoans in the gut of termites are the example [2012]
(a) Symbiosis (b) Parasitism
(c) Antibiosis (d) Commensalism

The formula for exponential population growth is [2013]
(a) dN/rN = dt (b) rN / dN = dt
(c) dN / dt = rN (d) dt / dN = rN

The rate of formation of new organic matter by rabbit in a grassland, is called [2014]
(a) Net productivity
(b) Secondary productivity
(c) Net primary productivity
(d) Gross primary productivity

If 4 individuals in a laboratory population of 40 fruitflies died during a specified time interval (i.e., a week), the death rate in the population during
that period is [2014]
(a) 1 (b) 0.1
(c) 0.01 (d) 0.4

A population of 500 that experiences 55 births and 5 deaths during a one-year period. What is the reproductive rate for the population during
the one-year period ? [2015]
(a) 0.01/year (b) 0.05/year
(c) 0.1/year (d) 50/year

The figure given below is a diagrammatic representation of response of organisms to abiotic factors. What do A, B and C represent respectively? [2015]

The salinity in sea water in parts per thousand (ppt) ranges between [2016]
(a) 5-15% (b) 30-35%
(c) 50-75% (d) more than 100%

In Urn shaped age pyramid of the population the trend of growth is [2017]
(a) Rapid (b) Stable
(c) Declining (d) Stationary

ASSERTION REASON QUESTIONS

Directions for (Qs. 1-3) : These questions consist
of two statements, each printed as Assertion and Reason. While answering these questions, you are required to choose any one of the following five
responses.
(a) If both Assertion and Reason are correct and the Reason is a correct explanation of the Assertion.
(b) If both Assertion and Reason are correct but Reason is not a correct explanation of the Assertion.
(c) If the Assertion is correct but Reason is incorrect.
(d) If both the Assertion and Reason are incorrect.
(e) If the Assertion is incorrect but the Reason is correct.

1-Assertion : Leaf butterfly and stick insect show mimicry to dodge their enemies.
Reason : Mimicry is a method to acquire body colour blending with the surroundings. [2003]

2-Assertion : Animals adopt different strategies to survive in hostile environment.
Reason : Praying mantis is green in colour which merges with plant foliage. [2004]

3-Assertion : The sex ratio of Kerala is highest in India.
Reason : In countries like India the population is increasing at a rapid rate. [2005]

Directions for (Qs. 26-30) : Each of these questions contains an Assertion followed by Reason. Read them carefully and answer the question on the basis of following options. You have to select the one that best describes the two statements.
(a) If both Assertion and Reason are correct and Reason is the correct explanation of Assertion.
(b) If both Assertion and Reason are correct, but Reason is not the correct explanation of Assertion.
(c) If Assertion is correct but Reason is incorrect.
(d) If both the Assertion and Reason are incorrect.

1-Assertion : Thick cuticle is mostly present in disease resistant plants.
Reason : Disease causing agents cannot grow on cuticle and cannot invade the cuticle.[2012]

2-Assertion : In sigmoid growth curve, population finally stabilizes itself.
Reason : Finally, the death rate increases than the birth rate. [2013]

3-Assertion : Tropical rain forests are disappearing fast from developing countries such as India.
Reason : No value is attached to these forests because these are poor in biodiversity.[2015]

4-Assertion : Flora contains the actual account of habitat and distribution of plants of a given area.
Reason : Flora helps in correct identification. [2016]

5-Assertion : Species are groups of potentially interbreeding natural populations which are isolated from other such groups.
Reason : Distinctive morphological characters are displayed due to reproductive isolation. [2017]

CHAPTER-36:Ecosystem

MULTIPLE CHOICE QUESTIONS

The food chain in which microbes breakdown energy rich compounds synthesized by producers is called [1999]
(a) ecosystem
(b) parasitic food chain
(c) detritus level chain
(d) predator food chain

10 % law of energy transfer was given by
(a) Lindemann (b) Tansley [2000]
(c) Stanley (d) Darwin

Food chain starts with [2000]
(a) autotrophs (b) herbivores
(c) carnivores (d) decomposers

Flora and fauna in lake or ponds is [2000]
(a) lentic biota (b) lotic biota
(c) abiotic biota (d) field layer

The enzyme responsible for the reduction of molecular nitrogen to the level of ammonia in the leguminous root nodule is [2000]
(a) nitrogenase (b) nitrate reductase
(c) nitrite reductase (d) ammoneases

The role of bacteria in carbon cycle is [2000]
(a) photosynthesis
(b) chemosynthesis
(c) decomposition of organic compounds
(d) evolution of O2

Trophic levels are formed by : [2001]
(a) plants
(b) animals
(c) organisms linked in food chain
(d) carnivores

Desert can be converted into green land by planting [2001]
(a) oxylophytes (b) psammophytes
(c) halophytes (d) trees

Mr. X is eating curd/yoghurt. For this food intake in a food chain Mr. X should be considered as occupying [2003]
(a) first trophic level
(b) second trophic level
(c) third trophic level
(d) fourth trophic level

Given below is one of the types of ecological pyramids. This type represents [2005]

(a) pyramid of numbers in a grassland
(b) pyramid of biomass in a fallow land
(c) pyramid of biomass in a lake
(d) energy pyramid in a spring

The function of leghaemoglobin during biological nitrogen fixation in root nodules of legumes is to [2006]
(a) convert atmospheric N2 to NH3
(b) convert ammonia to nitrite
(c) transport oxygen for activity of nitrogenase
(d) protect nitrogenase from oxygen

An ecosystem, such as an aquarium, is selfsustaining if it involves the interaction between organisms, a flow of energy, and the presence of [2009]
(a) equal numbers of plants and animals
(b) more animals than plants
(c) materials cycles
(d) pioneer organisms

The graph below shows the changes in two populations of herbivores in a grassy field. A possible reason for these changes is that [2009]

(a) all of the plant populations in this habitat decreased.
(b) population B competed more successfully for food than population A did.
(c) population A produced more offspring than population B did.
(d) population A consumed the members of population B.

A scorpion stalks, kills, and then eats a spider. Based on its behavior, which ecological terms describe the scorpion? [2009]
(a) producer, herbivore, decomposer
(b) producer, carnivore, heterotroph
(c) predator, carnivore, consumer
(d) predator, autotroph, herbivore

In the vast marine ecosystem, certain sea develop red colouration. This red colour is due to the presence of large population of which one of the following organisms? [2009]
(a) Trichodesmium erythrium
(b) Physarium
(c) Dinoflagellates
(d) Diatoms and members of red algae

The xerophytic plants conserve water by storing it in [2009]
(a) intercellular spaces
(b) normal parenchymatous cells
(c) intercellular spaces and parenchymatous cells
(d) parenchymatous cells specialized for this purpose

Most of the desert plants bloom during night time because [2010]
(a) their blooming is controlled by low temperature.
(b) they are sensitive to the phases of moon.
(c) the desert insects eat away flowers during day time.
(d) the desert insects are active during night time.

Whale is [2012]
(a) Primary producer
(b) Carnivorous, secondary consumer
(c) A decomposer
(d) Herbivorous

Which one of the following is not a function of an ecosystem? [2013]
(a) Energy flow (b) Decomposition
(c) Productivity (d) Stratification

How much portion of the Photosynthetically Active Radiation (PAR) is captured by the plants? [2016]
(a) 5 – 10% (b) 7 – 10%
(c) 8 – 10% (d) 2 – 10%

Arrange the following ecosystems in increasing order of mean NPP (Tonnes / ha / year)
A. Tropical deciduous forest
B. Temperate coniferous forest
C. Tropical rain forest
D. Temperate deciduous forest [2017]
(a) B < A < D < C
(b) D < B < A < C
(c) A < C < D < B
(d) B < D < A < C

Directions for (Q. 1) : These questions consist of two statements, each printed as Assertion and Reason. While answering these questions, you are required to choose any one of the following five responses.
(a) If both Assertion and Reason are correct and the Reason is a correct explanation of the Assertion.
(b) If both Assertion and Reason are correct but Reason is not a correct explanation of the Assertion.
(c) If the Assertion is correct but Reason is incorrect.
(d) If both the Assertion and Reason are incorrect.
(e) If the Assertion is incorrect but the Reason is correct.

1-Assertion: Insectivorous habitat of plants is to cope up O2 deficiency.
Reason: Insectivorous plants are partly autotrophic and partly heterotrophic. [1998]

Directions for (Qs. 23-28) : Each of these questions contains an Assertion followed by Reason. Read them carefully and answer the question on the basis of following options. You have to select the one that best describes the two statements.
(a) If both Assertion and Reason are correct and Reason is the correct explanation of Assertion.
(b) If both Assertion and Reason are correct, but
Reason is not the correct explanation of Assertion.
(c) If Assertion is correct but Reason is incorrect.
(d) If both the Assertion and Reason are incorrect.

1-Assertion : A network of food chains existing together in an ecosystem is known as food web.
Reason : An animal like kite cannot be a part of a food web. [2006, 2008, 2011]

2-Assertion : Pyramid of energy may be upright or inverted. [2011]
Reason: Only 20% of energy goes to next trophic level.

3-Assertion : Biotic community has higher position than population in ecological hierarchy.
Reason : Population of similar individuals remains isolated in the community. [2012]

4-Assertion : Net primary productivity is gross primary productivity minus respiration.
Reason : Secondary productivity is produced by heterotrophs. [2013]

5-Assertion : Net primary productivity is gross primary productivity minus respiration.
Reason : Secondary productivity is produced by heterotrophs. [2016]

6-Assertion : In a food chain, members of successive higher levels are fewer in number.
Reason : Number of organisms at any trophic level depends upon the availability of organisms which serve as food at the lower level.
[2003, 2017]

CHAPTER-37: Biodiversity and its Conservation

MULTIPLE CHOICE QUESTIONS

Heavy rainfall during summer produces [1998]
(a) desert (b) grassland
(c) forest (d) wetland

The trees occurring in two seasons is the characteristic feature of [1998]
(a) temperate deciduous forest
(b) tropical savannah
(c) grassland
(d) coniferous forest

The map given below indicates the former and the present distribution of an animal. [2003]

Which animal could it be?
(a) Wild ass (b) Nilgai
(c) Black buck (d) Lion

If the high altitude birds become rare or extinct, the plants which may disappear along with them are [2004]
(a) pine (b) oak
(c) orchids (d) Rhododendrons

Which one of the following is a pair of endangered species? [2004]
(a) Garden lizard and Mexican poppy
(b) Rhesus monkey and sal tree
(c) Indian peacock and carrot grass
(d) Hornbill and Indian aconite

Which one of the following is correct matching of a plant, its habit and forest type where it normally occurs? [2005]
(a) Prosopis, tree, scrub
(b) Saccharum officinarum, grass, forest
(c) Shorea robusta, herb, tropical rain forest
(d) Acacia catechu, tree, coniferous forest

One of the ex-situ conservation methods for endangered species is [2005]
(a) wildlife sanctuaries
(b) biosphere reserves
(c) cryopreservation
(d) national parks

Genetic diversity in agricultural crops is threatened by [2005]
(a) introduction of high yielding varieties.
(b) intensive use of fertilizers.
(c) extensive intercropping.
(d) intensive use of biopesticides

The Montreal protocol refers to [2006]
(a) persistent organic pollutants
(b) global warming and climate change
(c) substances that deplete the ozone layer
(d) biosafety of genetically modified organisms

Biosphere reserves differ from National parks and Wildlife sanctuaries because in the former [2006]
(a) human beings are not allowed to enter.
(b) people are an integral part of the system.
(c) plants are paid greater attention than the
animals.
(d) living organisms are brought from all over
the world and preserved for posterity.

Which part of the world has a high density of organism? [2007]
(a) Deciduous forests
(b) Grasslands
(c) Tropical rain forests
(d) Savannahs

Beta diversity is diversity [2007]
(a) in a community
(b) between communities
(c) in a mountain gradient
(d) on a plain

Which one of the following pairs of geographical areas show maximum biodiversity in our country ? [2008]
(a) Sunderbans and Rann of Kutch
(b) Eastern Ghats and West Bengal
(c) Eastern Himalaya and Western Ghats
(d) Kerala and Punjab.

A tree species in Mauritus failed to reproduce because of the extinction of a fruit-eating bird. Which one of the following was that bird? [2010]
(a) Dove (b) Dodo
(c) Condor (d) Skua

Tectonic is the study of [2011]
(a) volcanos (b) earth’s crust
(c) sand dunes (d) Sun

If the Bengal tiger becomes extinct [2004, 2012]
(a) Hyenas and wolves will become scare
(b) The wild area will be safe for man and domestic animals
(c) Its gene pool will be lost for ever
(d) The population of beautiful animals like deers will be stabilized.

Which of the following is considered a hot-spot of biodiversity in India ? [2013]
(a) Indo-Gangetic Plain
(b) Eastern Ghats
(c) Aravalli Hills
(d) Western Ghats

The largest Tiger reserve in India is [2014]
(a) Nagarhole
(b) Valmiki
(c) Nagarjunsagar-Srisailam
(d) Periyar

Using the figure, determine the percentage of bird species that will be lost if the island’s inhabitable land area is reduced from 100,000 km2 to 1 km2.

A : Island land area (km2) [2016]
(a) 17 percent of the bird species will be lost.
(b) 20 percent of the bird species will be lost.
(c) All of bird species will be lost.
(d) 93 percent of the bird species will be lost.

Directions for (Q. 1) : These questions consist of two statements, each printed as Assertion and Reason. While answering these questions, you are required to choose any one of the following five responses.
(a) If both Assertion and Reason are correct and the Reason is a correct explanation of the Assertion.
(b) If both Assertion and Reason are correct but Reason is not a correct explanation of the Assertion.
(c) If the Assertion is correct but Reason is incorrect.
(d) If both the Assertion and Reason are incorrect.
(e) If the Assertion is incorrect but the Reason is correct.

1-Assertion : In tropical rain forests. O-horizon and A-Horizon of soil profile are shallow and nutrient-poor.
Reason : Excessive growth of micro-organisms in the soil depletes its organic content.[2006]

Directions for (Qs. 1-5) : Each of these questions contains an Assertion followed by Reason. Read them carefully and answer the question on the basis of following options. You have to select the one that best describes the two statements.

(a) If both Assertion and Reason are correct and Reason is the correct explanation of Assertion.
(b) If both Assertion and Reason are correct, but Reason is not the correct explanation of Assertion.
(c) If Assertion is correct but Reason is incorrect.
(d) If both the Assertion and Reason are incorrect.

1-Assertion : Tropical rain forests are disappearing fast from developing countries such as India.
Reason : No value is attached to these forests because these are poor in biodiversity. [2012, 2013]

2-Assertion : Diversity observed in the entire geographical area is called gamma diversity.
Reason : Biodiversity decreases from high altitude to low altitude. [2014]

3-Assertion : A sanctuary is formed for the conservation of animals only.
Reason : Restricted human activities are allowed in sanctuaries. [2014]

4-Assertion: Communities that comprise of more species tend to be more stable.
Reason: A higher number of species results in less animal variation in total biomass. [2017]

CHAPTER-38: Environmental Issues

MULTIPLE CHOICE QUESTIONS

Which of the following is biodegradable pollutant? [1997]
(a) Plastic (b) Asbestos
(c) Sewage (d) Polythene

Positive pollution of soil is due to [1997]
(a) reduction in soil productivity
(b) addition of waste to soil
(c) excessive use of fertilizers
(d) all of the above

Which of the following metal pollution causes sterility in human beings? [1998]
(a) Mercury (b) Arsenic
(c) Manganese (d) Chromium

Which of the following is dissolved in water to make Bordeaux mixture ? [1998]
(a) Calcium chloride (b) Copper sulphate
(c) Sodium chloride (d) None of these

Acid rain is due to pollution of [2000]
(a) dust (b) pesticides
(c) SO2 and NO2 (d) carbon particle

Deforestation causes [2001]
(a) soil erosion (b) soil pollution
(c) noise pollution (d) air pollution

Green mufler is useful against [2002]
(a) air pollution
(b) noise pollution
(c) soil pollution
(d) radioactive pollution

In almost all Indian metropolitan cities like Delhi, the major atmospheric pollutant(s) is / are[2003]
(a) suspended particulate matter (SPM)
(b) oxides of sulphur
(c) carbon dioxide and carbon monoxide
(d) oxides of nitrogen

Photochemical smog formed in congested metropolitan cities mainly consists of [2003]
(a) ozone, peroxyacetyl nitrate and NOx
(b) smoke, peroxyacetyl nitrate and SO2
(c) hydrocarbons, SO2 and CO2
(d) hydrocarbons, ozone and SOx

Biological Oxygen Demand (BOD) is a measure of [2003]
(a) industrial wastes poured into water bodies
(b) extent to which water is polluted with organic compound
(c) amount of carbon monoxide inseparably combined with haemoglobin
(d) amount of oxygen needed by green plants during night

Drinking of mineral water with very low level of pesticides (about 0.02 ppm) for long periods may [2003]
(a) produce immunity against mosquito
(b) cause leukemia (blood cancer) in most people
(c) cause cancer of the intestine
(d) lead to accumulation of pesticide residues in body fat

Minimata disease is pollution related disease. It results from [2001, 2004]
(a) oil spills in sea
(b) DDT pollution
(c) release of industrial waste containing mercury in fishing water
(d) accumulation of arsenic

organic waste may result in [2004]
(a) drying of the lake very soon due to algal bloom
(b) an increased production of fish due to lot of nutrients
(c) death of fish due to lack of oxygen
(d) increased population of aquatic food web organisms

Nitrogen oxides, produced from the emission of automobiles and power plants, are the source of fine air borne particles which lead to [2004]
(a) photochemical smog
(b) dry acid deposition
(c) industrial smog
(d) wet acid deposition

Formation of non-functional methaemoglobin causes blue-baby syndrome. This is due to [2005]
(a) excess of arsenic concentration in drinking water
(b) excess of nitrates in drinking water
(c) deficiency of iron in food
(d) increased methane content in the atmosphere

Pollution from animal excreta and organic waste from kitchen can be most profitably minimized by [2006]
(a) storing them in underground storage tanks
(b) using them for producing biogas
(c) vermiculture
(d) using them directly as biofertilizers

Which one of the following is an environmentrelated disorder with the correct main cause? [2006]
(a) Black lung disease (pneumoconiosis) found mainly in workers in stone quarries and crushers.
(b) Blue baby disease (methaemoglobinaemia) due to heavy use of nitrogen rich fertilizers in the area.
(c) Non-Hodgkin’s Lymphoma found mainly in workers involved in manufacture of neem based pesticides.
(d) Skin cancer mainly in people exposed to benzene and methane.

Ozone in stratosphere extends [2007]
(a) 10-20 km (b) 20-25 km
(c) 15-30 km (d) 25-40 km

Which one of the following organisms is likely to show the highest concentration of DDT, once it has been introduced into the ecosystem?
[2010]
(a) Grasshopper (b) Toad
(c) Snake (d) Cattle

Which one of the following statement pertaining to pollutants is correct? [2011]
(a) DDT is a non-biodegradable pollutant
(b) Excess fluoride in drinking water causes osteoporosis hardening of bones, stiff joints
(c) Excess cadmium in drinking water causes black foot disease
(d) Methylmercury in water may cause “Itai Itai” disease

In the environment, ozone is known for its
(a) Harmful effects [2012]
(b) Useful effects
(c) Both (a) and (b)
(d) Inert nature

Which one of the following statement is true? [2013]
(a) The greater the BOD of waste water, more is its polluting potential.
(b) The greater the BOD of waste water, less is its polluting potential.
(c) The lesser the BOD of waste water, more is its polluting potential.
(d) The lesser the BOD of waste water, less is its polluting potential.

Which one of the following pairs is mismatched?
(a) Fossil fuel burning – release of CO2[2013]
(b) Nuclear power – radioactive wastes
(c) Solar energy – green house effect
(d) Biomass burning – release of CO2

The two gases making the highest relative contribution to the greenhouse gases are [2014]
(a) CO4 and CH4 (b) CH4 and N2O
(c) CFCand N2O (d) CO2 and N2O

A lake near a village suffered heavy mortality of
fishes within a few days. Consider the following
reasons for this:

  1. Lots of urea and phosphate fertilizer were used in the crops in the vicinity
  2. The area was sprayed with DDT by an aircraft
  3. The lake water turned green and stinky
  4. Phytoplankton populations in the lake declined initially thereby greatly reducing photosynthesis.
    Which two of the above were the main causes of fish mortality in the lake? [2015]
    (a) 2 and 3 (b) 3 and 4
    (c) 1 and 3 (d) 1 and 2

DDT residues are rapidly passed through food chain causing biomagnification because DDT is [2015]
(a) moderately toxic
(b) non-toxic to aquatic animals
(c) water soluble
(d) lipo soluble

Two lakes, A and B are identical in all aspects except that lake A has higher temperature.
Which of the following is true ? [2016]
(a) A has higher rate of oxygen dissolution.
(b) B has higher rate of oxygen dissolution.
(c) Oxygen dissolution of both is the same.
(d) Both the lakes have same BOD.

Euro II norms stipulate that sulphur be controlled at ppm in diesel and ppm in petrol. [2017]
(a) 350; 150 (b) 150; 350
(c) 350; 250 (d) 150; 250

ASSERTION REASON QUESTIONS

Directions for (Qs. 1-10) : These questions consist of two statements, each printed as Assertion and Reason. While answering these questions, you are
required to choose any one of the following five responses.
(a) If both Assertion and Reason are correct and the Reason is a correct explanation of the Assertion.
(b) If both Assertion and Reason are correct but Reason is not a correct explanation of the Assertion.
(c) If the Assertion is correct but Reason is incorrect.
(d) If both the Assertion and Reason are incorrect.
(e) If the Assertion is incorrect but the Reason is correct.

1-Assertion : Inhabitants close to very busy airports are likely to experience health hazards.
Reason : Sound level of jet aeroplanes usually exceeds 160 dB. [2003]

2-Assertion : Organochlorine pesticides are organic compounds that have been chlorinated.
Reason : Fenitrothion is one of the organochlorine pesticides. [2003]

3-Assertion : Agricultural output increased
several times after introduction of DDT.
Reason : DDT was the first insecticide used on a wide scale.[2004]

4-Assertion : A suspended particulate matter (SPM) is an important pollutant released by diesel vehicles.
Reason : Catalytic converters greatly reduce pollution caused by automobiles. [2005]

5-Assertion : Presently, the global atmosphere is warming up.
Reason : The depletion of stratospheric ozone layer has resulted in increase in ultraviolet radiations reaching the earth. [2005]

6-Assertion : Deforestation is one main factor contributing to global warming.
Reason : Besides CO2, two other gases methane and CFCs are also included under green house gases. [2006]

7-Assertion : UV radiation causes photodissociation of ozone into O2 and O, thus causing damage to the stratospheric ozone layer.
Reason : Ozone hole is resulting in global warming and climate change. [2006]

8-Assertion : The concentration of methane in the atmosphere has more than doubled in the last 250 years.
Reason : Wetlands and rice fields are the major sources of methane. [2006]

9-Assertion (A) : Pollution is always caused by human activities.
Reason (R) : Pollution is not different from contamination. [2007]

10-Assertion (A) : Chlorofluorocarbons are responsible for ozone depletion.
Reason (R) : Ozone level decreases by as much as 67% every year. [2007]

Directions for (Qs.1-5) : Each of these questions contains an Assertion followed by Reason. Read them carefully and answer the question on the basis of following options. You have to select the one that best describes the two statements.
(a) If both Assertion and Reason are correct and Reason is the correct explanation of Assertion.
(b) If both Assertion and Reason are correct, but
Reason is not the correct explanation of Assertion.
(c) If Assertion is correct but Reason is incorrect.
(d) If both the Assertion and Reason are incorrect.

1-Assertion : Secondary succession takes place in recently denuded area. [2009]
Reason : It is caused due to baring of an area.

2-Assertion : Excess of nitrates in drinking water are harmful for infants. [2009]
Reason : Nitrates are responsible for blue baby syndrome.

3-Assertion : Water pollutants are measured by BOD.
Reason : If BOD is more, the water is polluted. [2013]

4-Assertion : Methane, component of green house gases, contributing to global warming is about 20 percent.
Reason : Introduction of multi-point fuel injection engines in automobiles has decreased methane content in the exhausts.[2005, 2015]

5-Assertion : Eutrophication shows increase in productivity in water. [2013, 2017]
Reason : With increasing eutrophication, the diversity of the phytoplankton increases.