Previous Year Questions

QUESTION ID:2

A football player injured in the heat of play did not feel pain until the game was over. This stress-induced analgesia was explained by the following proposed statements:

A. The release of norepinephrine from brain stem catecholaminergic neurons in the amygdala reduced during stress

B. The reduced release of 2-arachidonoglycerol (2AG) in brain contributed to stress-induced analgesia

C. The inhibition of CB, receptors in many brain regions accounted for reduced analgesia in stress

D. The activation of CB2 receptors on microglia in stress caused analgesic effect Which one of the following options represents both correct statements?

QUESTION ID:3

Humans exposed to cold climate are able to maintain their body temperature. The physiological mechanisms operating in the condition were suggested in the following statements:

A. The increased thermogenesis in brown adipose tissue occurred in cold

B. Uncoupling protein 1 in brown adipose tissue participated in the increased heat production

C. The decreased secretion of catecholamine in cold elevated heat production

D. The reflex responses activated by cold were controlled from the anterior hypothalamus E. The counter-current exchanges of temperature between warm arterial blood flowing towards limbs and the cold venous blood coming from extremities conserved body heat. Which one of the following options represents a combination of INCORRECT statements?

QUESTION ID:4

The blood forced into aorta during systole sets up a pressure wave that travels along arteries (arterial pulse wave). The following figure depicts the pressure wave recorded from an artery during a cardiac cycle and the table below represents points in the graph (column A) and associated features (column B).

Which one of the following options represents a correct match between all terms of columns A and B?

QUESTION ID:5

A patient with primary hyper-aldosteronism develops diabetic glucose tolerance. Following statements are proposed on the patho-physiological condition of the patient:

A. the increase of serum potassium inhibits insulin secretion

B. the depletion of serum potassium decreases insulin secretion

C. the depletion of sodium decreases insulin secretion

D. thiazide diuretics worsen the condition of this patient Which one of the following options represents a combination of correct statements?

QUESTION ID:6

Certain statements made on the mechanisms of action of a neuro-hormone, vasopressin(VP) are given below:

A. VP acts on collecting ducts of kidney to concentrate urine by binding to V2 receptors and activating CAMP cascade

B. VP acts on collecting ducts of kidney to concentrate urine by binding to V2 receptors and activating CAMP cascade

C. VP acts on blood vessels to produce constriction by binding to V2 receptors and activating CAMP cascade

D. VP acts on blood vessels to produce constriction by binding to V2 receptors and activating phosphatidylinositol cascade Which one of the following options represents a combination of correct statements?

QUESTION ID:7

Given below are some statements made on the buffering capacity of hemoglobin (Hb) in contributing to acid-base balance in the body.

A. Hb buffering capacity is due to large number of histidine residues

B. Imidazole groups of Hb dissociate less than those of oxyhemoglobin (HbO2)

C. Hb buffering capacity is due to large number of threonine residues

D. Hb is a strong acid Which one of the following options represents a combination of correct statements?

QUESTION ID:8

Two petite yeasts, Mat-a and Mat-α are crossed. The diploid is grande. After a few mitotic divisions, the grande diploid is sporulated. The analysis of a large number of tetrads yielded a 2:2 ratio of petite: grande. A few potential scenarios describing the reason for this segregation pattern are stated below:

 A. The parental strains had two different mitochondrial rho- mutations

 B. One of the parents had a recessive nuclear petite mutation

 C. Only one of the mitochondrial petite mutation is inherited in the tetrads

 D. The mitochondria inherited are wild type. Which one of the following options represents a combination of all correct statements?

QUESTION ID:9

The following derivations are made from the pedigree chart:

 A. The trait can be Y-linked because I-parent produced II-4 child

B. The trait cannot be X-linked recessive because II-4 parent produced III-1 and III -3children

C. The trait can be X-linked dominant because I-1 parent produced II-5 child

D. The trait is unlikely to be autosomal recessive because II-6 and II-7 parents producedIII-4 child.

E. The trait may be autosomal dominant

The given pedigree shows the inheritance of a trait

Which one of the following options represents a combination of all correct statements?

QUESTION ID:10

DNA from a bacterial strain with genotype at b+c +d+e +f + was isolated and used to transform a strain of bacteria with genotype a-b-c -d-e - f - . The transformed cells were tested for the presence of co-transformed genes and the following types of co-transformants were observed: a + and c+ e+ and d+ d+ and b+ b+ and f+ c+ and e+ The correct order of genes will be:

QUESTION ID:11

In a plant, male sterility is caused by the presence of a dominant allele for a nuclear gene (Ms). There are also lines which carry a gene whose dominant allele (F) restores male fertility. These are called restorer lines. A cross is made between a male sterile line and a homozygous restorer line which does not contain the Ms allele. Of the F1 progeny, only those that carry the Ms allele are allowed to self-pollinate. What is the probability of obtaining a male sterile line in the resulting F2 progeny? (The Ms and F genes assort independently).

QUESTION ID:12

A protein has Gly at position 28 (wild type). On mutagenesis, a point mutation leads to conversion of Gly to Arg at position 28 (mutant 1). When mutant 1 is further rmutagenized, four different point mutants (mutants 2 to 5) were isolated where the Arg atposition 28 was mutated to Ile, Thr, Ser or Gly as represented below:

Based on the codons given in the table above, which one of the following codons codesfor Gly at position 28 of the wild type protein?

QUESTION ID:13

In a flower species, light pink locus is hypostatic to pigment development locus. R is for pigment development and W for light pink. The recessive allele (w) in light pink locus gives red colour and recessive allele in pigment locus (r) gives white colour. What will be the phenotype of W/-, r/r and w/w, r/r?

QUESTION ID:14

In most angiosperms, flowers have a perianth that consists of whorls of organs. Select the statement that is INCORRECT about the floral organs in angiosperms.

QUESTION ID:15

Given below are some statements related to bacterial toxins.

A. Exotoxins are usually heat stable proteins secreted by bacteria.

B. Exotoxins are usually heat labile proteins secreted by bacteria.

C. Endotoxins are heat stable lipopoly-saccharideprotein complexes of the outer membrane of gram-negative bacteria.

D. Endotoxins are heat labile lipoproteins of the outer membrane of gram-negative bacteria. Which one of the following options represents combination of correct statements?

QUESTION ID:16

The names of some specialized organs/structures are given in Column A and their location in organisms are given in Column B.

Select the correct matches:

QUESTION ID:17

Following diagram shows phylogeny of plants, fungi, and animals:

In the above diagram A, B, C and D represent; respectively;

QUESTION ID:18

Which of the following events/examples represent observation of evolutionary changes on a human time scale? Here human time scale is defined by an average human age of approximately 70-80 years.

QUESTION ID:19

Below is a table showing the number of species and actual food web links observed in three different ecosystems.

By calculating connectance as a measure of relative complexity of food webs, infer which of the following statements is correct?

QUESTION ID:20

Suppose a population has three age classes. Females in the second and third age classes produce four and three off springs, respectively. While 50% female in the first age class survive into the second age class, only 30% females survive into the third age class. The 

If there are 10 individuals in each of the three age classes, the number of individuals in the next iteration would be:

QUESTION ID:21

Which among the following sets of conditions are best suited for a mimic species to coexist with its model?

QUESTION ID:22

A small number (approx. 10) of mice are introduced into an uninhabited island. Their population grows exponentially initially and after 4 years, reaches a population size of 520 after which the population stays stable. At what point would you expect the population to attain its highest growth rate?

QUESTION ID:23

Two islands (A and B) located approximately 180 km and 100 km respectively from the mainland. Island A is 160 sq. km, while Island B is 220 sq. km in area. Which one of the following statements is correct?

QUESTION ID:24

Predator-prey interactions in a community are represented in the figure below. 

Given below are some statements related to the above figure:

(i) Predators and prey are generalists

(ii) Predators have expanded their prey base over time

(iii) Predators and prey have co-evolved

(iv) There is speciation in prey while predators are prone to extinction Which one of the following options represents statement/s that can be correctly inferred from the figure?

QUESTION ID:25

Given below are some examples of biological rhythms in humans: (a) REM and non-REM sleep cycle (b) Menstrual cycle (c) Sleep-wake cycle Which one of the following is a correct representation of the type of biological rhythms given above?

QUESTION ID:26

Given below are examples of animals and their behaviours.

A. Elephant :Innate and learnt behaviour

B. Ant: Innate behaviour only

C. Whale: Learnt behaviours only

D. Bee: Innate and learnt behaviours

Which one of the following options represents a correct combination of true and false?

QUESTION ID:27

Male fiddler crabs with larger claws are preferred by females over males with smaller claws. If the selection pressure exerted on claw size is strong, which one of the following options is true with respect to male claw size over generations?

QUESTION ID:28

Match the geological time period with the diversification events associated with them:

QUESTION ID:29

The table below shows the number of unrooted and rooted trees generated when the number of taxa are

three and four, respectively. Number of taxa Number of unrooted trees Number of rooted trees?

The number of rooted trees generated when there are five taxa is:

QUESTION ID:30

In a large, healthy, polygynous population of an ungulate species with distinct, short seasonal mating, the operational sex ratio (Male: Female) is likely to resemble which one of the following conditions:

QUESTION ID:31

Given below are four statements regarding the use of marker assisted selection (MAS) in plant breeding.

A. Markers that are not linked to target traits cannot be used to test accumulation of the desired recurrent parent's genetic background in a

backcross breeding program.

B. Co-dominant markers are more effective for marker assisted backcrossing since they facilitate selection of heterozygous progeny.

C. MAS can be used to facilitate backcrossing of recessive genes that influence traits of interest.

D. Use of tightly linked flanking makers for a trait of interest increases linkage drag in a breeding program.

Which one of the following options represents a combination of all INCORRECT statements?

QUESTION ID:32

Duschenne muscular dystrophy (DMD) is caused by a defective dystrophin gene and can be cured by removing a specific faulty exon. If a CRISPR/Cas9

based genome editing approach is to be designed to remove the faulty exon, some of the following conditions have to be met.

A. Two guide RNA molecules to match the flanking regions of the faulty exon

B. An efficient non-homologous end joining system in the host

C. Two separate, specific Cas9 endonucleases to target both ends of the exon

D. A single guide RNA that targets the intron preceding the exo

Choose the option that includes all the correct conditions.

QUESTION ID:33

In a gene stacking experiment, a transgenic plant generated using bar as a selection marker was crossed with another transgenic line containing hpt as the selection marker. Analysis of the Fı progeny of this cross showed that 50% of the progeny was resistant to both selection agents (Basta and hygromycin) while the remaining 50% of the progenywas resistant to only hygromycin. Which one of the following statements is a possible explanation of the above results?

QUESTION ID:34

Column A lists names of microorganisms and column B lists the pollutants that are degraded by the microbes.

Which one of the following options correctly matches the organism to the pollutant it most commonly degrades?

QUESTION ID:35

The table given below lists animals and primary regions of domestication

Which one of the following options represents the best match for animals and the primary region of their domestication?

QUESTION ID:36

For ELISPOT measurements of interferon g [IFN-g] secretion by mouse NKT cells, the following steps were performed in an ELISA plate:

A. Addition of purified spleenocytes

B. Stimulation of spleenocytes by peptide pulsed antigen presenting cells (APCs)

C. Addition of biotin-conjugated anti IFN-g antibody

D. Addition of capture antibody specific to IFN-g

E. Addition of avidin-conjugated colour changing substrate.

Which one of the following options lists the correct sequence of steps performed?

QUESTION ID:37

Given below are four statements on various methods used in molecular biology and recombinant DNA studies:

A. Orientation of a cloned DNA fragment in a plasmid vector can be determined by using primers specific to the cloned fragment.

B. Transcriptome sequencing cannot be used to identify differential expression profiles of mRNA in an organism.

C. A DNA fragment with 5' overhangs can be converted into a blunt-ended fragment by using a nuclease but not by a DNA polymerase

D. Oligonucleotide probes can be labelled at their 5 and 3' ends by using T4polynucleotide kinase and terminal transferase, respectively

Which one of the following options consists of only correct statement/s?

QUESTION ID:38

A student hypothesized that protein Yfg100 interacted with protein Yfr70 in a tissue-specific manner. To test this, an immune precipitation experiment was performed using antibodies to Yfg 100 and the samples were subjected to western blot using antibodies to both Yfg100 and Yfr70. The results obtained are shown below

Based on the results shown, identify the INCORRECT statement

QUESTION ID:39

To spatiotemporally detect the localization of two proteins A and B using a confocal microscope, an investigator plans to utilize a few fluorescent proteins

(X, Y, Z and T).The excitation and emission spectra of these fluorescent proteins are shown below.

Which one of the following options comprises of a fluorescent pair that is best suited to conduct such an experiment?

QUESTION ID:40

Following are statements related to spectroscopic investigation of proteins.

A. Tryptophan fluorescence in a protein is not sensitive to its environment.

B. Observation of a large number of N; - Ni+1 connectivity’s in the NOESY spectrum of a protein suggests the presence of helical conformation.

C. Only proteins with masses less than 5000 daltons can be identified by MALDI mass spectrometry.

D. Protein conformation can be investigated by ESI mass spectrometry.

Which one of the following options consists of both correct statements?

QUESTION ID:41

Following are statements related to statistical methods:

 A. An outlier can be defined as a value in a data set that lies more than three standard deviations from the mean.

 B. Measures of central tendency and dispersion are independent of the presence of outliers in a data set.

 C. Standard deviation is a measure of dispersion.

 D. Mean, median and mode are not measure of central tendency.

 Which one of the following options is a combination with both INCORRECT statements?

QUESTION ID:42

Given below are sampling techniques and their features.

Which one of the following options correctly matches sampling techniques with their features?