Previous Year Questions

QUESTION ID:2

In a transformation experiment, donor DNA from an E. coli strain with the genotypes Z+Y+ was used to transform a strain of genotype Z- Y-. The frequencies of transformed classes were:
Z+Y+      200
Z+Y-       400
Z-Y+      400
Total      1000
What is the frequency (%) with which Y locus is cotransformed with the Z locus?

QUESTION ID:3

The ‘Tribe” refers to a taxonomic group recognized between the

QUESTION ID:4

A plant species has been descrobe for the fisrt time by a author “x”. Later, the species has been transferrred to some other genys by author “y”. Then the author citation for the new combination will be

QUESTION ID:5

The group which is no longer considered under the fungi is

QUESTION ID:6

Character similarity that can be misinterpreted as common descent is called

QUESTION ID:7

The following table shows survival and fertility data for a seasonally breeding species. Based on above data net reproductive rate (Ro) of the species will be Season Proportion Surviving Fertility

QUESTION ID:8

Which of the following is NOT a characteristic of late successional forest plant species?

QUESTION ID:9

Which of the following organism do not possess the ability to fix nitrogen?

QUESTION ID:10

Which of the following greenhouse gases has got highest atmospheric life time?

QUESTION ID:11

Which of the following evolutionary processes played an important role in the evolution of immune system?

QUESTION ID:12

In some species of new world monkeys, only one female reproduces in a group. One or more younger females have suppressed reproduction and asssit the reproductive female. This is an example of

QUESTION ID:13

In bird species where both parents contribute equally to parental care, generally

QUESTION ID:14

The idea that an altruistic gene will be favored if r>C/B, where r is the coefficient of relatedness, B is the benefit to the recipient of the altriusm, and c is the cost incurred to the donor, is known as

QUESTION ID:15

Usse of double haploids in plant breeding helps to

QUESTION ID:16

For sustainable expression of a trangene in the successive generation of a cell line in culture, the ideal gene transfer can be obtained using

QUESTION ID:17

Desulphovibrio desulfuricans (A) and Pseudomonas species (B) are involved in mercury bioremediation. Which of the statement below is correct?

QUESTION ID:18

Optical density of a 400 base pair llong 1 ml DNA solution was found to be 0.052. How many DNA molecules are present in the solution? [1 base pair=650 dalton, optical density of 1.0 D corresponds to 50 μg DNA/ml]

QUESTION ID:19

In which of the following techniques does molecular fragmentation offer clues to the covalent chemical structures of biomolecules?

QUESTION ID:20

The movement of a single cell was required to be continually monitored during development. This cell was marked with a reporter gene. To visualize this movement one would use

QUESTION ID:21

The Gibbs free energy of binding of a ligand with a protein is determined using calorimetric measurements at 25°C. The value of ΔGo thus determined is 1.36 kcal/mole. The binding constant for the ligand-protein association is:

QUESTION ID:22

A is converted to E by enzymes EA, EB, EC, ED. The Km(M) values of the enzymes are 10-2, 10-4, 10-5 and 10-4, respectively. If all the substrates and products are present at a concentration of 10-4 M, and the enzymes have approximately the same Vmax the rate limiting step will be

QUESTION ID:23

The molecular mass of a protein determined by gel filtration is 120 kDa. When its mass is determined by SDS.PAOE with and without β-mercaptoethanol, it is ooly 60 kDa. What is the most probable explanation for these observations?

QUESTION ID:24

Mouse IgG is left either intact (left lane A,B,C, D) or digested with papain or pepsin or treated with β-mercaptoethanol (β- ME) and run on non-reducing SDS-PAGE and stained with Coomassie blue. In a separate experiment, papain-digested products are immunoblotted with an anti-idiotypic monoclonal antibody. Following four profiles are attributed to each of these treatments. Which one of the following possibilities is correct?

QUESTION ID:25

The citric acid cycle in respiration yields:

QUESTION ID:26

Phosphatidyl serine (PS) is mostly located in the inner bilayer of plasma membrane of red blood cells (RBCs). You have to prove this fact about PS by an experiment. You are provided with PS-specific lytic enzymes (PSE) and other reagents needed. Identify the correct sequence of experiments to be carried out to settle this issue.

QUESTION ID:27

ATP-driven pumps hydrolyze ATP to ADP and phosphate and use the energy released to pump ions or solutes across a membrane. There are many classes of these pumps and representatives of each are found in all prokaryotic and eukaryotic cells. Which of the following statements about these pumps is NOT correct?

QUESTION ID:28

Following are statements related to the organization of the four major protein complexes of thylakoid membrane,
A. Photosystem II is located predominantly in the stacked regions of the thylakoid membrane.
B. Photosystem I is found in the unstacked regions protruding into stroma.
C. Cytochrome B6f complex is confined to stroma only.
D. ATP synthase is located in the unstacked regions protruding into stroma.
Which one of the following combinations of above statements is correct?

QUESTION ID:29

A bacterial population has a plasmid with copy number 'n'. It was observed that on an average in one out of 2(n-1) cell divisions, there was spontaneous plasmid curing. It was inferred from the observation that:
A. Each cell division does not have equal probability of plasmid curing.
B. There is no evidence for any mechanism of plasmid segregation in the two daughter cells.
C. Plasmid distribution to daughter cells is random.
D. Each plasmid has an equal chance of being in either of the two daughter cells.
Which of the combinations of above statements is true?

QUESTION ID:30

In a given experiment the cells were labeled for 30 minutes with radioactive thymidine. The medium was then replaced with that containing unlabelled thymidine and the cells were grown for additional time. At different time points after replacement of medium the fraction of mitotic cells were analysed. Based on the results obtained, the above figure was drawn which shows the percentage of mitotic cells that are labeled as a function of time after brief incubation with radioactive thymidine.

Considering the above experiment, the following statements were made:

A. Cells in the S-phase of the cell cycle during the 30 minute labeling period contain radioactive DNA.
B. It takes about 3 hours before the first labeled mitotic cells appear.
C. The cells enter the second round of mitosis at t30 hours.
D. The total length of the cell cycle is about 27 hours with G1, being more than 15 hours.
Which of the combination of above statements is correct?

QUESTION ID:31

Mutants of lac Y (Y-) gene of E. coli do not synthesize the lactose permease protein. The following statements refer to the behaviour of lac Y- mutants under different experimental conditions.
A. No synthesis of β- galactosidase when Y' cells are induced with lactose.
B. Synthesis of β- galactosidase when cells are induced with lactose.
C. No synthesis of β- galactosidase when cells are induced with IPTG.
D. Synthesis of β- galactosidase when cells are induced with IPTG.
E. The cells induced with IPTG cannot grow in the presence of TONPG (TONPG is a compound, whose uptake is mediated by lactose permease and cleaved by β- galactosidase to release a toxic compound).
F. Cells induced with IPTG Can grow in the presence of TONPG.
Which combination of the above statements is correct?

QUESTION ID:32

The semi-conservative nature of DNA replication was established by Meselson and Stahl in their classic experiment with bacteria. They grew bacteria in N15-NH4Cl containing medium, washed and then incubated in fresh medium with N14- containing compounds and allowed to grow for three generations. CsCl density gradient centrifugation of isolated DNA established the nature of semiconservative DNA replication. The pictorial representation below shows the
position of differentially labeled DNA in CsCl density gradient. Had the DNA replication been conservative, what would have been the pattern?

QUESTION ID:33

HeLa cell extract was used to study transcription of a gene ‘X’ having six introns. RNA Pol II complex containing all associated proteins was isolated from actively transcribing system and subjected to proteome analysis. Results showed the presence of both splicing and capping enzymes in the complex. When transcription elongation was inhibited by flavopiridol, polymerase complex contained only capping enzymes. When phosphorylation of the CTD domain of Pol II was inhibited by a kinase inhibitor, the complex contained neither splicing nor capping enzymes. From these results, following conclusions were made:
A. Transcription of gene X is coupled to mRNA capping.
B. Transcription elongation is coupled to splicing.
C. Phosphorylation of CTD is required for the recruitment of capping and splicing enzymes.
D. Both capping and splicing of mRNAs occurs simultaneously. Identify the correct set of conclusions:

QUESTION ID:34

In bacteria, N-formyl methionine is the first amino acid to be incorporated into a polypeptide chain. Accordingly, one would think that all bacterial proteins have a formyl group at their amino terminus and the first amino acid is methionine. However, this is not the case, because of the following possible reasons.
A. Deformylase removes the formyl group only during or after the synthesis of the polypeptides.
B. Aminopeptidase removes only the amino terminal methionine.
C. Aminopeptidase removes the amino terminal methionine as well as one or two additional amino acids.
D. Deformylase removes the formyl group as well as amino terminal methionine and adds one or two amino acids to it.
Choose the combination of comet answers from the following:

QUESTION ID:35

Bacteriophage λ is a temperate phage. Immediately after infection, viral specific mRNAs for N and Cro proteins are expressed followed by early mRNAs. At the commitment phase, either lytic cycle starts with the expression of genes for head tail, and lytic proteins or lysogenisation cycle begins with the expression of repressor and integrase genes. During induction of lysogens both INT and XIS proteins are needed along with host factors. Out of the four processes below, some govern Integration of viral genome and its excision?
A. Repression of transcription
B. Retroregulation
C. Rearrangement of viral genome
D. Repression of translation
Identify the correct set of combination:

QUESTION ID:36

In E. coli, recA gene is involved in recombination as well as repair and dnaB gene is involved in unwinding of DNA double strands during replication. Which of the following statement is/are correct about Rec A and Dna B?
A. Mutation in E. coli recA gene is lethal.
B. E. coli with mutated dnaB gene does not survive.
C. Dna B after uncoiling DNA double strands, prevents further reannealing at the separated strands.
D. Rec A gene is involved in SOS response and helps DNA repair.
The correct options are:

QUESTION ID:37

The challenges faced by aminoacyl tRNA synthetases in selecting the correct amino acid is more daunting than its recognition of the appropriate tRNA. In case of amino acids with similar structures like valine and isoleucine, this challenge is met by the enzyme possibly through its
A. catalytic pocket. B. editing pocket.
C. anticodon loop. D. acceptor arm.
Choose the correct set from the following:

QUESTION ID:38

p24 is an important core protein of HIV. This protein is abundant during active replication of the virus. The serum of an HIV patient was examined for the presence of p24 and antibody against p24 for proper diagnosis of the infection stage. Match the clinical observations in column A with the inferences in column B. Choose the correct matching

QUESTION ID:39

Epidermal growth factor (EGF) is needed for growth of almost all cells. EGF receptor is a transmembrane protein having an extracellular ligand-binding domain, a transmembrane domain and a cytosolic domain of protein tyrosine kinase (PTK). Binding of EGF to the receptor activates PTK resulting in  activation of transcription factors through intracellular transducers. In cell type A, much of the extra cellular ligand-binding domain is deleted by proteases such that cytosolic domain of PTK becomes constitutively active whereas cell type B is having normal EGF receptor. What will be the best-fit graph for the growth of the cultures of cell type A and B in complete medium in presence (+) and absence (-) of EGF'? 

QUESTION ID:40

A particular type of cancer cell undergoes apoptosis by both extrinsic and intrinsic pathways when treated with a chemotherapeutic agent X. Caspase 8 and Caspase 9 are the initiator caspases associated with extrinsic and intrinsic pathways respectively. Now, if caspase 9 is silenced in the cancer cell by shRNA transfection, what will be the best fit graph for apoptosis scenario in the cancer cell when treated with agent X?

QUESTION ID:41

After successive surgery and chemotherapy, the tumor of a breast cancer patient subsided. However after almost 5 years, the tumor relapsed in a more aggressive manner and did not respond to the conventional chemotherapy delivered earlier. The following postulations were made.
A. Chemoresistant cells were persisting within the tumor even after therapy.
B. A population of quiescent cells existed, which under favourable conditions, transformed to new tumor cells.
C. High ABC (ATP-Binding Cassette) transporter expressing cells persisted in the breast during chemotherapy.
D. Breast tumor cells which may have migrated to other tissues, returned to the breast immediately after chemotherapy was terminated.
Which of the above combination of statements is true?

QUESTION ID:42

Following are the experimental observations made on treatment of B cells:
A. Anti-immunoglobulin (anti-Ig) antibody treatment results in B cell apoptosis.
B. Anti-Ig plus CD40 ligand treatment results in B cell proliferation.
C. Anti-Ig plus CD40 ligand plus IL-4 treatment results in B cell proliferation and switching to IgG1.
D. Anti-Ig plus IL-4 treatment results in less B cell proliferation but switching to IgE.
From the above observation, which one of the following is the
correct interpretation for the role of CD40 in B cell function?

QUESTION ID:43

A potentially valuable therapeutic approach for killing tumor cells without affecting normal cells is the use of immunotoxins. Immunotoxins constitute monoclonal antibodies against tumor cells conjugated to lethal toxins. Which of the following molecular approaches do you think is NOT appropriate for generating tumor cell-specific immunotoxin that will not kill normal cells?

QUESTION ID:44

Flowers represent a complex array of functionally specialized structures that differ substantially from the vegetative plant body in form and cell types. Following are statements made regarding floral meristems.
A. Floral meristems can usually be distinguished from vegetative meristems by their larger size.
B. The increase in the size of the meristem is largely a result of increased rate of cell division in central cells.
C. The increase in the size of the meristem is due to larger size of the cells, which in turn results from rapid cell expansion only.
D. A network of genes control floral morphogenesis in plants.
Which combination of the above statements is true?

QUESTION ID:45

Three embryos, X (wild type), Y (mutant for bicoid) and Z (mutant for nanos) were injected with bicold mRNA in their posterior pole at early cleavage stage. What would be the phenotypes of the resulting embryos? 

QUESTION ID:46

In C. elegans during embryogenesis, an anchor cell and 6 hypodermal vulval precursor cells (VPCs) get involved in forming the vulva. If 3 of the hypodermal VPCs are killed by a laser beam, a normal vulva is still formed. This could be due to the following possible reasons.
A. Six hypodermal VPCs form equivalence group of cells, out of which only 3 participate in vulva formation and 3 cells remain as reserve cells.
B. When 3 hypodermal VPCs are killed, the 3 neighboring hypodermal non- VPCs get freshly recruited.
C. Anchor cell functions as an inducer which can induce epithelial cells of the gonad to gel recruited to compensate for the loss.
D. Anchor cell acts as an inducer which can spatially induce only 3 hypodermal cells to form the vulva.
Which combination of the above statements is correct?

QUESTION ID:47

In tadpoles, if the tail is amputated it can regenerate. However, if the tail is amputated and then exposed to retinoic acid, it develops limbs instead of regenerating the tail. This could be due to the following reasons:
A. Retinoic acid is a morphogen and induces genes responsible for limb formation.
B. Retinoic acid raises the positional values in that region for limb development to take place.
C. This is a random phenomenon and is not well understood.
D. Retinoic acid possibly acts as a mutagen and the phenotype observed is a result of several mutations.
Which combination of the above statements is true?

QUESTION ID:48

In sea urchins, a group of cells at the vegetal pole become specified as the large micromere cells. These cells are determined to become skeletogenic mesenchyme cells that will leave the blastula epithelium to ingress into the blastocoel. This specification is controlled by the expression of Pmar1 which is a repressor of HesC. HesC represses the genes encoding transcription factors activating skeleton forming genes. The gene regulatory network is given below.

Below, column I lists the experiments carried with mRNA/antisense RNA of different genes injected into singlecelled sea urchin embryo while column II lists the developmental outcomes: Match the following: Which of the following combinations is correct?

QUESTION ID:49

Which of the following cellular communications shown below will override the process of normal development and lead to cancer?
 

QUESTION ID:50

In plants, the energy of sunlight is first absorbed by the pigments present in their leaf cells followed by the fixation of carbon through photosynthesis. Consider the following statements.
(A) Chlorophylls a and b are abundant in green plants.
(B) Chlorophylls c and d are found in some protists and cyanobacteria.
(C) Out of different types of bacteriochlorophyll, type a is the most widely distributed.
(D) Out of different types of bacteriochlorophyll, type b is the most widely distributed.
Which one of the following combination of above statements is correct?

QUESTION ID:51

Nitrate reductase is an important enzyme for nitrate assimilation. Given below are some statements on nitrate reductase enzyme:
(A) Nitrate reductase of higher plants is composed of two identical subunits.
(B) One subunit of nitrate reductase contains three prosthetic groups.
(C) One of the prosthetic groups attached to both subunits is heme.
(D) One of the prosthetic groups complexed with pterin is magnesium.
Which one of the following combination of statements on nitrate reductase mentioned above is correct?

QUESTION ID:52

A farmer growing a particular variety of grape plants in vineyard, observes the following:
(A) Fruit size normally remained small.
(B) Natural seed abortion.
(C) Development of fungal infection as the pedicels are small in size due to which moisture is retained in the bunches of grapes.
Experts suggested spraying gibberellic acid during the fruit development. This treatment would help in getting rid of

QUESTION ID:53

Light is perceived by various photoreceptors in plants. The photoreceptors predominantly work at specific wavelengths of light. Some of the following statements are related to the functions of plant photoreceptors.
(A) Phytochrome A predominantly perceives the red and farred light.
(B) Phytochrome B predominantly perceives red light.
(C) Cryptochromes regulate plant development.
(D) Phototropins are involved in blue light perception and chloroplast movements.
Which one of the following combinations based on above statements is correct?

QUESTION ID:54

From the following statements:
(A) Triose phosphate is utilized for the synthesis of both starch and sucrose.
(B) Triose phosphate is translocated to cytosol from chloroplast.
(C) Triose phosphate is confined to chloroplast and is utilized for synthesis of starch only.
(D) Triose phosphate is translocated from cytosol to chloroplast.

Which one of the following combinations is correct regarding starch and sucrose synthesis during day time?

QUESTION ID:55

Shown above, is a graph representing the growth of different plant species subjected to salinity relative to that of unsalinized control. Which of the following statements is NOT true?
 

QUESTION ID:56

An experimentalist stimulates a nerve fibre in the middle of an axon and records the following observations. Which one of the observation is correct?

QUESTION ID:57

Desert animals have longer loop of Henle compared to that of humans. It may be due to the following reasons:
A. Long loop of Henle is associated with greater amount of vasopressin secretion.
B. In long loop of Henle, the counter-current exchanger is more effective.
C. Long loop of Henle conserves more water.
D. Long loop of Henle stimulates production of angiotensin II.
Which of the above reason(s) is/are correct?

QUESTION ID:58

A boy eats a large serving of cheese having high amount of sodium. He hardly drinks any fluid. Inspite of this, the water and electrolyte balance was maintained. Which one of the following explanation is correct?

QUESTION ID:59

The blood volume decreased when a mammal was bled rapidly. However, the cardiovascular changes resulting from hemorrhage could be minimized by the following compensatory mechanisms:
A. Increased cerebral blood flow,
B. Reduction of baroreceptor activity and stimulation of chemoreceptors.
C. Reabsorption of tissue fluid in blood.
D. Increased release of enkephalins and beta-endorphins.
Which of the above is/are correct?

QUESTION ID:60

The stomach of a person was partially removed during surgery of a gastric tumour. Despite taking a balanced diet, the person developed anemia. Following possible explanations were offered:
A, Lower gastric secretion inhibits folic acid absorption
B. Protein digestion was disturbed in partial gastrectomy
C. Lower HCl secretion from stomach reduced iron absorption
D. Lower secretion of intrinsic protein factor from stomach reduced VitB absorption
Which of the above explanations were correct?

QUESTION ID:61

The RFLP pattern observed for two pure parental lines (P1 and P2) and their F1 progeny is represented below. Further, the PI plant had red flowers while the P2 had white flowers. The F1 progeny was backcrossed to P2. The result obtained, showing the number of progeny with red and white flowers and their RFLP patterns is also represented below Which one of the following conclusions made is correct?

QUESTION ID:62

Wild type T4 bacteriophage can grow on B and K strains of E. coli forming small plaques. rll mutants of T4 bacteriophage cannot grow on E. coli strain K (non-permissive host), but form large plaques on E. coli strain B (permissive host). The following two experiments were carried out:
Experiment I: E. coli K cells were simultaneously infected with two rII mutants (a- and b-). Several plaques with wild type morphology were formed.
Experiment II: E. coli B cells were simultaneously infected with the same mutants as above. T4 phages were isolated from the resulting plaques and used to infect E. coli K cells. Few plaques with wild type morphology were formed.

Which one is the correct conclusion made regarding the rII mutants, a- and b- from the above experiments?

QUESTION ID:63

The following pedigree represents inheritance of a trait in an extended family:

What is the probable mode of inheritance and which individuals conclusively demonstrate this mode of inheritance?

QUESTION ID:64

Following is the diagram of a paracentric inversion heterozygote ABCDEFG/ABFEDCG involved in recombination during meiosis I: The consequence of this recombination will be the formation of

A. A dicentric and an acentric chromosome in meiosis I as the chiasmata gets terminated.
B. No dicentric or acentric chromosome but appearance of deletion and duplication in both the chromosomes.
C. All non-viable gametes.
D. Non-viable gametes from crossover products.
Which of the above statements are correct?

QUESTION ID:65

An E. coli strain has metB1 (90 min) and leuA5 (2 min) mutations. It also has strA7 (73 min) mutation and Tn5 transposon which confers streptomycin and kanamycin resistance, respectively, inserted in its chromosome. The mutant strain was crossed with an Hfr strain that is streptomycin sensitive and has a hisG2 mutation (44 min) that makes it require histidine. After incubation for 100 min, the cells were plated on minimal plate supplemented with leucine,
histidine and streptomycin to select the metB marker. After purifying 100 of the Met+ transconjugants, one finds that 15 are His+, 2 are Leu+ and 12 are kanamycin sensitive. The unselected markers are
A. metB1 and leuA5 mutation.
B. leuA5 and Tn5 insertion mutation.
Which of the above statement is correct and what is the position of transposon insertion?

QUESTION ID:66

chemist synthesized three new chemical compounds, M1, M2 and M3. The compounds were tested for their mutagenic potential and were found to be highly mutagenic. Tests were made to characterize the nature of mutations by allowing the reversion with other mutagens. The following results were obtained:
Which one of the following conclusions drawn regarding the nature of mutations by the compounds is correct?
 

QUESTION ID:67

Four Cnidarians with the following characteristics were observed:
A. Asexual polyps and sexual medusae; solitary or colonial; both freshwater and marine.
B. Polyp stage reduced or absent, medusae with velum; solitary; all marine.
C. Polyp stage reduced, bell shaped medusae; solitary; all marine.
D. All polyps, no medusae; solitary or colonial; all marine. They can be identified to their respective classes:

QUESTION ID:68

The following table shows the summary of characters between two taxa based on presence (1) and absence (0) data
Which of the following represents Jaccard's coefficient and Simple matching coefficient respectively?

QUESTION ID:69

Identify the proteobacteria based on the key given below:
i. Cause disease in humans                                 (ii)
i. Do not cause disease in humans                    (iii)
ii. An obligate intracellular parasite                   (A)
ii. Not all obligate intracellular parasite             (B)
iii. Live in insects                                                   (C)  
iii. Do not live in insecls                                       (iv)
iv. Chemoautotrophic                                          (D)
iv. Not Chemoautotrophic                                   (v)
v. Plant pathogen                                                (E)
v. Not a plant pathogen                                     (vi)
vi. Fix nitrogen                                                     (vii)
vi. Do not fix nitrogen                                         (F)
vii. Associated with legumes                             (G)
vii. Not associated with legumes                       (H)

QUESTION ID:70

Which of the following phylogenetic trees appropriately uses principle of parsimony? 

QUESTION ID:71

Identify the characters shown in the diagram depicting phylogenetic relationships among major groups of ferns and fern allies.

QUESTION ID:72

Associate the forest/vegetation type with the plants:
a. Grass land
b. Subalpine forest
c. Shola forest
d. Subtropical pine forest
e. Tropical thorn forest
f. Tropical dry deciduous forest
g. Tropical semievergreen forest
h. Tropical wet evergreen forest

QUESTION ID:73

Possible explanations for the age related decline in primary productivity of trees are:
A. As trees grow larger with age, they have more tissues that respire and loose energy and proportionately less leaf area to photosynthesis.
B. Nutrient limitation by nitrogen due to reduced rate of woody litter decomposition as forest ages.
C. As trees become larger, water transport to the top canopy leaves becomes limited because of increased hydraulic resistance. This results in reduced stomatal conductance and reduction in photosynthetic rate.

Which of the above is/are correct?

QUESTION ID:74

 Species characteristics that make them more prone to extinction are listed below:
A. High degree of specialization
B. High sexual dimorphism
C. High trophic status
D. Short life span
Which of the following is the correct combination?

QUESTION ID:75

Based on the information given in the table below, which combination is correct?

QUESTION ID:76

In a census for a lake fish, 10 individuals were marked and released. In second sampling after a few days 15 individuals were caught, of which 5 individuals were found marked. The estimated population of the fish in the lake will be

QUESTION ID:77

Identify the pollinators for the flowers with following pollination syndromes
A. Flowers dull colored, located away from foliage, floral parts turgid,
B. Flowers bright red, crowded, turgid, neclar watery and sucrose rich.
C Flowers white with pleasant odor, corolla tube long, night blooming.

QUESTION ID:78

Which of the following combinations is good for setting up a nature reserves:
 

QUESTION ID:79

If the number of new species evolving is directly proportional to the number of existing species and the probability of extinction of any species is inversely proportional to the number of existing species, the number of species present at a time during evolution will follow a curve given by: 

QUESTION ID:80

If the relationship between life time reproductive success and body size for males and females of a species as shown in figure below:
The species is most likely to evolve
 

QUESTION ID:81

Following tree represents phylogenetic relationships among species of a moth family. Circles represent species having eye spots on the wings. Other species do not have eye spots.

The following interferences were made by different researchers:
A. Eye spots were present in the ancestors and some species lost them.
B. Eye spots were not present in the ancestors.
C. Eye spots were lost more than once in evolution of the family.
D. Eye spots were gained only once while evolving from ancestors without them.
Which of the interferences are correct?
 

QUESTION ID:82

Wolbachia are obligate intracellular bacteria, many different strains of which are abundantly present in insects. They induce mating incompatibility in host, i.e. males infected with one strain can only fertilize females infected with the same strain. No other pathological effects are observed in host. A possible evolutionary consequence of this phenomenon would be:

QUESTION ID:83

Twenty small populations of a species, each polymorphic for a given locus (T, t) were bred in captivity. In 10 of them the population size was kept constant by random removal of individuals, while other 10 were allowed to increase their population size. After several generations it was observed that in 7 of the size restricted populations only T was present, in the remaining 3 only t was observed. The experiment illustrates

QUESTION ID:84

Some important events in the history of life on Earth are given below.
A. First vertebrates (jawless fishes); first plants.
B. Forest of ferns and conifers; amphibians arise; insects radiate.
C. Conifers dominant; dinosaurs arise; insects radiate.
D. Flowering plants appear; climax of dinosaurs followed by extinction.
E. Radiation of flowering plants, most modern mammalian orders represented.
F. Ice Ages, Modern humans appear
Match the above with the geological time periods and choose the correct combination,

QUESTION ID:85

Microbes produce either primary or secondary metabolites during fermentation. A metabolite production curve is shown below:
The following statements refer to the above figure:
A. A primary metabolite has a production curve that lags behind the line showing cell growth.
B. A primary metabolite is produced after the Trophophase is completed.
C. A secondary metabolite is produced mainly during Idiophase.
D. The curve shows the production of Penicillin from mold

Which of the above statements are correct?
 

QUESTION ID:86

During transgenesis, the location of the genes and their number integrated into the genome of the transgenic animal are random. It is often necessary to determine the copy number of genes and their tissue-specific transcription. The following are the possible methods used for the determination.
A. Polymerase Chain Reaction(PCR)
B. Southern blot hybridization
C. Reverse Transcriptase PCR
D. Western blot
Choose the correct set of combinations.

QUESTION ID:87

Agrobacterium tumefaciens, also known as natural genetic engineers, causes crown-gall disease in plants. However, when the same bacteria are used to raise transgenic plants with improved agronomic traits, no such tumor (disease) is observed. This is due to:
A. Vir D2 gene is mutated in Ti plasmid.
B. Disarmed Ti plasmid is generally used.
C. Heat-shock during transformation destroys virulence.
D. Oncogenes have been removed.
Which one of the following combination of above statements is correct?

QUESTION ID:88

Locus control region (LCR) lies far upstream from the gene cluster and is required for the appropriate expression of each gene in cluster. LCR regulates expression of globin genes in the cluster through the following ways.
A. LCR interacts with promoters of individual genes by DNA looping through DNA-binding proteins.
B. The LCR-bound proteins attract chromatin-remodeling complexes including histone-modifying enzymes and components of the transcription machinery.
C. LCR acts as an enhancer for global regulation of gene cluster and does not regulate individual genes.
D. LCR participates in covering inactive chromatin to active chromatin around the gene cluster.
Choose the correct set of combinations.

QUESTION ID:89

A student wrote following statements regarding comparison of Restriction Fragment Length Polymorphism
(RFLP), Random Amplified Polymorphic DNA (RAPD), Amplified Fragment Length Polymorphism (AFLP) and Simple Sequence Repeats (SSRs) techniques used for generating molecular markers in plants:
A. All these techniques can be used for fingerprinting.
B. Detection of allelic variation can be achieved only by RFLP and SSRs.
C. Use of radioisotopes is required in RFLP and RAPD only.
D. Polymerase chain reaction is required for all the techniques.
Which one of the following combination of above statements is correct?

QUESTION ID:90

In order to clone an eukaryotic gene in pBR322 plasmid vector, the desired DNA fragment was produced by PstI cleavage and incubated with PstI digested pRR322 (PstI cleavage site lies within the ampicillin resistant gene) and ligated. Mixtures of ligated cells were used to transform E. coli and plasmid containing bacteria were selected by their growth in tetracycline containing medium. Which type of plasmid/s will be found?

QUESTION ID:91

During apoptosis, phosphatidyl serine (PS) usually present in the inner leaflet of the plasma membrane flips to the outer membrane. Annexin V is a protein that binds to PS, Using this as a tool, we identifiy the apoptic cells from necrotic and normal cell populations by FACS using FITC-tagged Annexin V. Propidium iodide (PI) is used to stain the nucleus which generally identifies necrotic and late apoptic cells. In which
area of the plot you should get early apoptic cells by FACS analysis?

QUESTION ID:92

The muscle tone was increased after electrolytic lesion of the caudate nucleus in a cat. The muscle tone decreased within seven days. The following explanations were given by the researcher.
A. The functional recovery was due to plastic changes of nervous system.
B. The brain tissue surrounding the lesioned area was nonfunctional due to circulatory insufficiency immediately after surgery which led to the greater functional loss.
C. The circulatory status in surrounding tissue recovered with time resulting in partial functional recovery.
D. The degenerating nerve fibres were regenerated which underlie functional recovery.
Which one of the following is correct?

QUESTION ID:93

A fluorophore when transferred from solvent A to solvent B results in an increase in the number of vibrational states in the ground state without any change in the mean energies of either the ground or excited state. What would be the change seen in the fluorophore’s emission spectrum?

QUESTION ID:94

You wish to localise a given gene product at subcellular levels following immunofluoroscence staining. Routine microscopy could not resolve whether the gene product is localized inside the nucleus or on the nuclear membrane.
Which of the following will resolve this unambiguously?
A. Sectioning of cell followed by phase contrast microscopy.
B. A simulation of 3D picture following confocal microscopy.
C. Optical sectioning and observing each section.
D. Freeze fracturing followed by Scanning Electron Microscopy.

QUESTION ID:95

The Triver-Willard hypothesis states that the physiological state of a female can bias the sex ratio of offspring. In an experiment in the bird species a group of females were fed a diet 30% lower in calories than the control females. After allowing both the groups to mate and breed freely, the offspring of control 1 group were 22 males and 18 females. The diet restricted females laid a total of 40 eggs. What should be the minimum deviation from the control to conclude that they have significantly female biased offspring sex ratio. (Chi sq [0.05] df =1 is 3.84)