Previous Year Questions

QUESTION ID:2

In an experiment, the cells that would normally become the middle segment of a Drosophila leg were removed from the leg forming area of the larva and were placed in the tip of the fly's antenna. Based on the "French flag" analogy for the operation of a gradient of positional information, which of the following statements is true?

QUESTION ID:3

Which of the inferences (A-D) given below would you draw from the following tissue transplantation experiments performed with the early and late gastrula stages of the newt?

(A) Cells of early newt gastrula exhibit conditional development.
(B) Cells of early newt gastrula exhibit autonomous development
(C) Cells of late newt gastrula exhibit conditional development.
(D) Cells of late gastrula exhibit autonomous development.
The correct inferences are:

QUESTION ID:4

Segmentation genes in Drossophila are divided into three groups (gap, pair rule and segment polarity) based on their mutant phenotype.  Below are some of the major genes expressed in a sequential ,manner (with respect to the groups) affecting segmentation pattern. Which of the above sequence(s) of genes expressed from early to late embryo is/are correct?

(A) hairy → paired → tailless → patched

(B) hunchback → even-skipped → fushi tarazu → wingless

(C) odd-skipped → giant → paired → wingless

(D) tailless → hairy →fushi tarazu → gooseberry

QUESTION ID:5

Human chorionic gonadotropin (hCG) is known to facilitate attachment of blastocyst to uterus. In women with mutation in hCG gene, biologically inactive hCG was formed but implantation occurred. When heG was immune-neutralized in the uterus of normal woman, implantation failed. This suggests that for implantation in humans:

QUESTION ID:6

During reproductive development in plants:
(A) male and female gametes are produced as a result of two mitotic divisions after meiosis
(B) vegetative cells in pollen contribute to pollen development
(C) antipodal provide nourishment to developing embryo
(D) Pollen tube ruptures and releases both the male gametes in one of the degenerated synergids
Which of the above statement are true?

QUESTION ID:7

During fertilization "in mammals, sperm-egg interaction is mediated by zona pellucida (ZP) membrane proteins and their receptors present in sperm membrane. ZP3 has been identified to be the principle ZP protein whose post-translational modification is important for sperm - egg interaction. In a competitive inhibition assay the sperm is saturated with either active ZP3 or its modified forms, before studying sperm-egg-interaction. Which of the following experiments will NOT inhibit sperm-egg-interaction  

QUESTION ID:8

If an Arabidopsis plant, mutated in lycopene biosynthetic pathway is grown in sunny tropical climate in the presence of oxygen:

QUESTION ID:9

According to the current model of alternative oxidase regulation, the following factors cause induction of alternative oxidase:
(A) significant increase in the ubiquitin pool in the cytosol.
(B) presence of α-keto acids (like pyruvate and glyoxylate).
(C) cold stress.
(D) increase in cytosolic ATP concentration.
Which one of the following combinations of above statements is true?

QUESTION ID:10

The oxidative pentose phosphate pathway provides the reducing equivalents for nitrite reduction in plastids (Ieucoplasts) of non-green tissues. Which one of the following statements would be correct for the above mentioned pathway?

QUESTION ID:11

Perception of blue light in plants causes

QUESTION ID:12

Following are few statements regarding water potential of soil.
(A) The osmotic potential (ψs) of soil water is generally negligible, except in saline soils.
(B) The osmotic potential (ψs) of saline soil is always more than zero.
(C) In dry soils the hydrostatic pressure (ψp) of soil water potential is always positive.
(D) Gravitational potential (ψg) of soil water is always proportional to height of the tree.
Which one of the following combinations of above statements is true?

QUESTION ID:13

Which One of the following pairs of precursor amino acid and alkaloid is correct?

QUESTION ID:14

Typical morphological defects are routinely used in genetic screens to identify novel genes in signal transduction pathways. Which one of the following morphology has been used to decipher the ethylene signaling pathways?

QUESTION ID:15

In bone marrow, stem cells are committed to different lineages. Factors that stimulate colonies of these different lineages are interleukin-3 (multi-CSF), granulocyte- macrophage colony stimulating factor (GMCSF) and granulocyte or macrophage colony- stimulating factor (G-CSF or M-CSF). In a mouse deficient in GM-CSF the number of hematopoietic cells will be altered. Which one of the following is correct?

QUESTION ID:16

An individual was suffering from digestive complications. It was observed that the individual had dehydrated gastrointestinal tract. When an advanced investigation was done, the person was found to have defects in the following:
(A) cystic fibrosis transmembrane conductance regulator protein.
(B) glucose transporter protein.
(C) Na + /K+ ATPase
(D) Ca2+ATPase
Which of the above could be the cause for such a digestive disorder?

QUESTION ID:17

The action potential was recorded intracellularly from a squid giant axon bathed in two types of fluid such as sea water and artificial sea water having lower concentration of sodium ions while maintaining the same osmotic pressure with choline chloride. The nature of action potential was different in the two bathing fluids. Which of the following results is most likely?

QUESTION ID:18

Three forms of dextrans namely neutral, polyanionic and polycationic having different molecular radii were injected separately in three groups of rats. The concentrations of dextrans in glomerular filtrate were measured to determine the filterability of the dextrans. The possible outcomes could be as follows:
(A) The dextrans having smaller diameter have greater filterability than larger dextrans.
(B) Neutral dextrans were filtered more than polycationic and polyanionic dextrans.
(C) Polycationic dextrans were filtered more than neutral and polyanionic dextrans.
(D) Polyanionic dextrans were filtered more than neutral and polycationic dextrans.
Which one of the following combinations is correct?

QUESTION ID:19

A novel enzyme was identified in humans. The following approaches are available to identify the chromosome on which the gene encoding the enzyme is present:
(A) Suppress the activity of enzyme by RNAi.
(B) Identify polymorphism in the population and carry out pedigree analysis to study its inheritance.
(C) Purify the enzyme, decipher its amino acid sequence, predict its DNA sequence and search for its presence in the available human genome sequence.
(D) Create chromosome addition lines by making somatic hybrids between human and mouse cells, identify lines showing the enzyme activity and the human chromosome present in it.
Which of the above approaches can be used?

QUESTION ID:20

In an experiment on transposition in an eukaryotic system, an intron was cloned within a transposable element and allowed to transpose from a plasmid to genomic DNA. The intron was found to be absent in the transposable element in its new location. It is

QUESTION ID:21

In a plant species, a segregating line (one that contains both homozygotes and heterozygotes at a locus) can be made homozygous by repeated selfing for several generations. What is the level of remaining heterozygosity after three generations of selting, if the level of heterozygosity in generation '0' is denoted as 1?

QUESTION ID:22

Given below, is the result of a complementation test for six independent mutants (1 to 6). '+' represents complementation; '0' represents noncomplementation Based on the above, which one of the following conclusions is correct?

QUESTION ID:23

In a hospital three babies were mixed up. The blood group of the babies were A, B and AB. In order to identify the parents of the babies, the blood groups of the parents were determined. The results obtained were:
Parent set 1 – A and AB
Parent set 2 – AB and O
Parent set 3 – B and AB
Which of the following conclusions can be definitively made?

QUESTION ID:24

There are two mutant plants. One shows taller phenotype than wild type, whereas the other has the same height as the wild type. When these two mutations were brought in together by genetic crosses, the double mutant displayed even taller phenotype than the tall mutant plants. This genetic interaction is called

QUESTION ID:25

The following table gives vascular tissue characteristics of four divisions of Tracheophyta

Identify the correct combinations:

QUESTION ID:26

Which of the following is NOT an advantage to seedbased reproduction?  

QUESTION ID:27

In a study of sexual isolation in a species of salamander, scientists brought together males and females from different populations and from the same population. They observed the frequency of mating and calculated a sexual isolation index. One graph shows the
relationship between mating frequency and genetic distance, and the other shows the relationship between sexual isolation index and geographic isolation.

Choose the appropriate terms for of X1, Y1, X2 and Y2 in the figures, above.
 

QUESTION ID:28

As per the of International Code of Botanical Nomenclature, 2006 (Vienna Code), which of the following is a Nothospecies?

QUESTION ID:29

Which of the following groups have only two wings?

QUESTION ID:30

India has currently 17 biosphere -reserves representing different ecosystems. These conservation areas significantly differ from the conventional protected areas of the country. Identify the correct combination of attributes (A to G) that best .explains the concept of
biosphere reserve.
(A) Conservation,
(B) Education,
(C) Human habitation allowed,
(D) Human habitation not allowed,
(E) Strong legal back-up,
(F) No supporting act,
(G) Research.

QUESTION ID:31

Followings are the niche characteristics of the constituent species and resource partitioning pattern in different ecosystems. Which of these would lead to competitive exclusion of species?

QUESTION ID:32

Environmental conditions can influence accumulation of species in successional communities. Curves representing changes in forest species over time are given in the figure below. Which of the following keys is correct for the curves?

QUESTION ID:33

A plant with blue-coloured flowers was observed to attract a large number of pollinators. However, these flowers were not producing any nectar. Which of the following can be a logical explanation to the observation?

QUESTION ID:34

Three islands have identical habitat characteristics. On first island rodent species A is present at a density 325/km2. Second island has only species B at a density of 179/km2. On the third island, both A and B co-exist with densities 297/km2 and 150/km2, respectively. Which of the following can be inferred from this?

QUESTION ID:35

A few males and females of a species were introduced to a new island. Their population was monitored over several .generations and followed a pattern shown in the figure. Which of the characteristics of the species does NOT explain the pattern?

QUESTION ID:36

Plasmids are self-replicating small circular DNA elements in bacterial cells that can be said to have a stable symbiotic existence with the host cell. They often carry genes useful to the host. Which of the following is a potential threat to the evolution and stability of the symbiotic coexistence?

QUESTION ID:37

Complex eukaryotic cells may have evolved from simpler prokaryotic cells because complexity of organization increases the

QUESTION ID:38

Knox gene code transcriptionl factor important for regulation of indeterminate growth in plant shoots. These genes also regulate patterns of development of plant organs such as leaves and flowers. The figure represents a phylogenetic tree of the multigene family in some land plants. The circles represents the genes that act to maintain shoot apical meristem (equivalent to stem cells). Orthologues are genes that duplicate due to speciation and paralogues are genes that duplicate within a species.

From the figure; the following inferences were made.

(A) Multiple gene duplication occurred in vascular plants.

(B) Gene duplications may have enabled shoot diversification in vascular plants.

(C) Shoot apical meristems are regulated by orthologous genes in vascular plants.

(D) Shoot apical meristems are regulated by paralogous genes in vascular plants.
Which of the following represents a combination of correct inferences?
 

QUESTION ID:39

In an experiment that has continued for more than 50 years, corn has been propagated by breeding only from plants with the height amount of oil in the seeds. The average oil content is now much greater than any of the plants in the original population. The following hypotheses were proposed as explanations for this observation.
(A) Mutations occurred that increased the oil content in seeds.
(B) Plants with high oil content were stimulated to produce offspring with more oil in their seeds.
(C) The breeding led to increased frequency of alleles at multiple loci, so that new combinations of genes for even higher oil content were formed.
Which of the following represents a combination of correct statements?

QUESTION ID:40

The Galapagos finches were an important clue to Darwin's thinking about the origin of species. These finches are believed to have descended from a single ancestral species that colonized the Galapagos archipelago, America, over a short period of time. The Galapagos finches differ in their beak shape and size. Different species feed on seeds that vary in size and  hardness. Which of the following is the most likely explanation for these patterns? 

QUESTION ID:41

In order to demonstrate that the long tails of males attracted females in a bird species, experimenters captured and cut the tails of 'n' number of males and monitored the number of females mated by each male. They had two types of controls in the experiment.
(i) 'n' males that were not captured
(ii)'n' males that were captured, had their tails cut and then stitched back to attain the original size. The males with cut tails mated with a significantly smaller number of females than both the controls. Which of the following alternative explanations is NOT ruled out by the, experiment?

QUESTION ID:42

In the phylogenetic tree above, branch-lengths are drawn proportional to the number of changes along a lineage.
The following inferences were made from this tree.
A.  Bacteria are more closely related to Eukarya than to Archaea.

B. Bacteria and Archaea are more similar to each other than either is to Eukarya.

C. Archaea and Eukarya diverged from each other after their common ancestor diverged from bacteria.

D. cells from two different plants can be mixed together and forced to fuse.

Which of the following represents a combination of correct inferences?

QUESTION ID:43

While attempting to create a disease model of poliomyelitis in mice, it was found that mice can not be infected with the said virus. Since human beings are susceptible to this viral infection, which kind of transgenic mice should be generated to have a transgenic mouse model that can be infected with polio virus? Select the right approach from below:

QUESTION ID:44

Protoplast fusion is used in plant tissue culture for various applications. In protoplast fusion:
(A) naked plant cells are used.
(B) transfer of organelles is not possible.
(C) partial genome transfer is involved.
(D) cells from two different plants can be mixed together and forced to fuse.
Which one of the following combinations of the above statements is correct?

QUESTION ID:45

Which of the following is a mismatch between the plant drug and its source?

QUESTION ID:46

Which of the following curves correctly represents the process of ethanol production by yeast?

QUESTION ID:47

Inbreeding for 5 generations led to production of homozygous transgenic mice. However, these homozygous males or females were infertile. Which of the following approach is most preferable and economical to obtain heterozygous transgenic animals continuously?

QUESTION ID:48

Following are few statements for regeneration of plants from explants/tissues.
(A) Cytokinin is required for shoot development.
(B) Auxin is required for shoot development.
(C) Auxin to cytokinin ratio is very important.
(D) Jasmonic acid is required for both root and shoot development.
Which of the following combinations of above statements is true?

QUESTION ID:49

A set of neonatal mice are divided into four groups. Group I neonates were not primed with any antigen. Group 2 neonates were primed with KLH. Group 3 neonates were primed with KLH but thymectomized. Group 4 neonates were KLH-primed, thymectomized, but reconstituted with KLH- specific CD4+ T cells. All these mice, when grown adult, were challenged with KLH and the anti-KLH IgO antibody was measured in sera. Which of the following is the collects order of magnitude of antibody response? [> = greater than, > = greater than or equal to]

QUESTION ID:50

Choose the correct sequence of events in a next generation sequencing technology-based whole genome sequencing project

QUESTION ID:51

An investigator discovers a new receptor for a known ligand and wanted to identify the binding partner of the receptor i.e. its co-receptor. The anti-receptor antibody is not available but anti GFP-antibody is available. Which one of the following strategies is most
likely to identify the co-receptor?

QUESTION ID:52

The frequency distribution of tree heights in two forest areas with different annual rainfall are given Which of the following statistical analysis will you choose to test whether rainfall has an effect on tree heights?
 

QUESTION ID:53

Two species of plants were sampled in 32 quadrats in a forest. The mean and variance for the occurrence of species 1 were 16.2 and 48 and species 2 were 3.6 and 3.2 respectively. Which of the following statements about the distribution of the two species in these quadrats is supported by these findings?  

QUESTION ID:54

Poly-L-Iysine exists in pure α-helix, β-sheet and random coiled conformation depending upon the solvent conditions. Tile values of mean residue ellipticity at 220 nm ([θ]220) are -35,700, -13,800 and +3,900 deg cm2 dmol-1 for α-helix, β-sheet and random coil
conformations of this polypeptide, respectively. The polypeptide exists in α- helix conformation at pH 10.8 and 250 C.
Addition of urea leads to a two state transition between α-helix and random coil conformation. It has been observed that [θ]222 of the polypeptide is -14800 degcm2dmol-1in the presence of 6M urea. The percentage of the polypeptide in α-helix conformation is:

QUESTION ID:55

Given below, is the result of a complementation test for six independent mutants (1 to 6)