Previous Year Questions

QUESTION ID:2

Three species M, N and O when grown independently in a laboratory showed typical logistic growth curves. However, when grown in pairs, the following growth curves were observed.  What interpretation regarding the interspecific relationship between M, N and O can be deduced from the above observations?

QUESTION ID:3

Temporal isolation in breeding seasons between closely related species leads to reproductive isolation. Given below are breeding seasons of different species of frogs.

Which of the above plots represents temporal isolation in breeding seasons among closely related sympatric species? 

QUESTION ID:4

Given below are the population pyramids of three different populations A, B and C depicting the relationship between birth and death rates in each. Based on the population pyramids given above, which one of the following is INCORRECT? 

QUESTION ID:5

Given below are names of some of the National Parks of India and their key protected animals. Based on the table given above, which of the following options represents the correct match? 

QUESTION ID:6

Given below are two patterns of ecological succession. Four species are represented by A, B, C and D. An arrow indicates “is replaced by”.

In the context of ecological succession, which of the following statements is INCORRECT with respect to the figures given above.

QUESTION ID:7

Given below are the species accumulation curves and rarefaction curves measured in an ecological community Which one of the following statements is INCORRECT about the two curves? 

QUESTION ID:8

A gene ‘X’ in Drosophila contributes to inviability of hybrids. The phylogeny below shows the evolutionary history of gene ‘X’ and on each branch the numbers indicate the non-synonymous/synonymous substitutions.

Based on the above information, select the correct statement from the choices below: 

QUESTION ID:9

When the electrical response of the two receptors A1 and A2 in a noctuid moth that was exposed to a variety of sounds was measured, it produced the following patterns:   Given this, which one of the following statements is INCORRECT: 

QUESTION ID:10

A barn owl sits on its perch 10m above ground. It hears a mouse underneath on the ground at an angle alpha as shown in the figure below. The error range with which it can locate the mouse on the ground is given by

QUESTION ID:11

A 20-week old infant was exposed to the following stimuli and the responses were measured.  Based on the response patterns shown above to the given stimuli, select the correct theory that best describes the observed responses. 

QUESTION ID:12

When James R Brown and W Ford Doolittle (1997) reconstructed the tree of life using a variety of different genes, they found that different genes gave fundamentally different phylogenies as shown below. Note that the genes are unique to the specific trees.

From the given options select the process that best explains the observed discrepancies between the trees. 

QUESTION ID:13

Orchids of the genus Cryptostylis are known to maintain reproductive isolation because their flowers look and smell like females of the wasps of genus Lissopimpla. When the male wasp visits and attempts to mate with the flower, the shape of anther and stigma allows correct placement and transfer of pollen to the wasp, which then transfers the pollen to species specific flower that it next attempts to mate with. This prezygotic barrier that prevents inter-species cross-pollination in Cryptostylis is best explained by: 

QUESTION ID:14

Some of the following transgenic approaches could be used for functional characterization of endogenous genes in plants:

A. Transformation using a binary vector containing a strong enhancer element and lacking the right border of T-DNA

B. Transformation using a binary vector containing a promoter-less reporter gene sequence and a selction maker gene cassette within the T-DNA.

C. Transformation using a binary vector containing only a strong enhancer element and a selection marker gene cassette within the T-DNA.

D. Transformation using a binary vector lacking a reporter gene as well as both the left and right borders of T-DNA.

Which one of the following combinations can be used?

QUESTION ID:15

Match the following Vir proteins with their correct function during Agrobacterium mediated transfer of T-DNA to plant cells.

QUESTION ID:16

Match the technique with its appropriate application/use from the list of options given below

QUESTION ID:17

A researcher attempted to clone a 630bp coding sequence of a gene downstream to a bacterial promoter (500bp in length) for over expression and purification of the encoded protein. The gene sequence was isolated as a SmaI fragment (Recognition sequence: CCCGGG; arrow indicates the site of restriction) and cloned at a SmaI site located downstream to the promoter. The gene sequence contained a single site for EcoRI located 30bp downstream to the start codon. A schematic representation of the plasmid along with locations(s) of some restriction enzyme sites of the vector is given below.

The researcher screened the obtained colonies by a double digestion using HindIII and EcoRI. Which one of the following restriction digestion patterns would represent the restriction profile of the desired clone that could be used for overexpression?

QUESTION ID:18

To achieve a best resolution using a fluorescence microscope, what combination of wavelength of emitted light (λ), refractive index and the angle (2θ) by which light enters into the microscope would be the best choice for the user: 

QUESTION ID:19

Given below are spatial and temporal techniques (column I) used to detect brain activity (column II)  Select the correct set of combination 

QUESTION ID:20

Following observations are made regarding a peptide sequence.

- The peptide is inert to Ellman’s reagent. However, on reacting with beta-mercaptoethanol, the peptide gives a positive Ellman’s test.

- The peptide sequence gives a broad minimum around 211 nm in the CD spectrum.

- With increasing concentration of the peptide, the melting temperature of the peptide increases.

- On treating the peptide with D2O, half the total number of amides get exchanged.

Which one of the following statements is correct?

QUESTION ID:21

If a metabolically active cell is challenged with 55Fe radioisotope label, which of the following proteins CANNOT be detected by autoradiography?

QUESTION ID:22

Diagnosis of influenza virus infections can be done using some of the following techniques:

A. Western blot and Southern blot

B. Northern blot and western blot

C. ELISA and RT-PCR

D. PCR and electron microscopy

Choose the combination of techniques that correctly lists the detection methods. 

QUESTION ID:23

From the following statements:

(A) Coloured images can be obtained by transmission electron microscopy by fluorescent labelling of the specimen

(B) Scanning electron microscopy requires sectioning of the sample

(C) Confocal microscopy uses optical methods to obtain images from a specific focal plane and excludes light from other planes

(D) Differential-interference microscopy relies on interference between polarized light due to differences in the refractive index of the object and surrounding medium

(E) Visualization in epifluorescence microscopy requires staining by heavy metal atoms

Choose the combination with two correct and one incorrect statements.