Previous Year Questions

QUESTION ID:2

The pedigree (Fig A) represents the inheritance of a monogenic disorder, caused by a defective enzyme encoded by a mutant allele. The functional and defective enzymes can be resolved by PAGE. The allozyme pattern observed in some of the individuals in the family is represented in Fig B. The frequency of the mutant allele in the population is 0.04.

Based on the above information, the following statements were made:

A. The allele encoding the functional enzyme is haiplo-sufficient.

B. The trait shows 100% penetrance.

C. The probability that a child born to individuals 11.3 and 11.4 will be homozygous for the gene is 1/4.

D. Both individuals 1.1 and 1.2 are necessarily heterozygous for the gene.

Which one of the following options correctly identifies each statement as True (T) or False (F) from A to D, respectively?  

QUESTION ID:3

Spindle assembly in animal cells requires nuclear envelope breakdown (NEBO). NEBO is a multistep process, which begins when Cdk1/cyclinB phosphorylates multiple components of the nuclear envelope. Given below are some components that are directly phosphorylated by Cdk1/cyclinB:

A. Nuclear Pore Complexes

B. Nuclear lamina

C. Greatwall kinase

D. Histone H3

Choose the option with correct Cdk1 /cyclinB substrate/s that are directly associated with NEBO. 

QUESTION ID:4

The following statements are made regarding apoptosis in the nematode, C. elegans:

A. The human ortholog of C. elegans, CED-9 is overexpressed in a 8-cell lymphoma.

B. A ced-9(gain-of-function);ced-3(loss-of-function) double mutant will have more than 947 non-gonadal cells.

C. If purified EGL-1 is added to a CEDF-9/CED-4 complex in vitro, the autocleavage of CED-3 does not occur.

D. CED-8 is a multi-spanning plasma membrane protein that is required for externalization of phosphatidylserine.

Which one of the following options represents all correct statements? 

QUESTION ID:5

Which statement about studies on succession is INCORRECT?

QUESTION ID:6

The table below shows types of chemical mutagens and names of mutagens.

Which one of the following options shows the correct match between Column X and Column Y?

QUESTION ID:7

The following statements are made about hematopoiesis in humans.

A. Bone marrow stem cells are not the source of osteoclast and mast cells.

B. Normally, three fourths of the cells in the marrow cavities mature to white blood cells and one fourth to red blood cells.

C. In adults, blood cells are not actively produced in the marrow cavities of all the bones.

D. Hematopoietic stem cells are derived from committed cells.

Which one of the following options represents all correct statements.? 

QUESTION ID:8

The statements below are made about some animal pathogens that may evade innate and inflammatory responses by the following mechanisms:

A. The flagellin of Proteobacteria has a mutation that prevents it from being recognized by Toll-like receptors (TLRs).

B. The lipopolysaccharides of He/icobacter have mutations that prevent it from being recognized by TLRs.

C. M. tuberculosis escapes from the phagosome to the cytosol, thereby avoiding degradatiorn by lysosomal enzymes.

D. Influenza virus produces Yop protein that inhibits inflammasome activity.

E. S. typhi encodes a protein that binds Type I IFNs and prevents them from binding to the IFN receptor.

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

QUESTION ID:9

Shown in the table below are the enzymes (Column X) involved in the biosynthesis of listed phytohormones (Column Y).

Which one of the following options represents all correct matches between Column X and Column Y? 

QUESTION ID:10

The helicase activity of E. coli DnaB was investigated using the following two substrates (I and II) under various conditions, followed by gel electrophoresis and autoradiography. The results of these experiments are depicted below:

The following statements are made purely from the results shown above:

A. DnaB can unwind only a partially unwound DNA.

B. SSB inhibits the unwinding activity of DnaB.

C. DnaB unwinds DNA in the 5 to 3' direction.

D. DnaB requires ATP for DNA unwinding.

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

QUESTION ID:11

The mRNA of the E.coli lac operon contains the open reading frames for lacZ, lacY, and lacA genes from a single cistron. It is observed that lacZ is translated more frequently than lacY or lacA. Which one of the following statements best describes the reason for this observation? 

QUESTION ID:12

The figure below depicts the feedback regulation in the biosynthesis pathway of three branched-chain amino acids (BCAA)- Leu, Val, and lie, acting at three major steps catalyzed by enzymes AHAS, I PMS, and TD. The activity of AHAS is feedback regulated by the synergistic combination of Leu and Val. IPMS activity is regulated exclusively by Leu. lle regulates TD activity while Val can relax this feedback regulation on TD by lle.

Which one of the following possibilities of BCAA pools is likely to occur in the RNAi knockdown of IPMS? 

QUESTION ID:13

Given below are different types of bacterial growth curves.

Which one of the following options represents all correct matches between the growth curves and the type of culture?  

QUESTION ID:14

The following statements are about parental care and variance in reproductive success in a bird species.

A. If females provide more parental care than males, the variance in male reproductive success is significantly greater than that of females.

B. Where only males provide parental care, the variance in female reproductive success is significantly higher than that of males.

C. In the case of biparental care, the variance in male reproductive success is significantly greater than that of females.

D. In the case of biparental care, the variance in female reproductive success is significantly greater than that of males.

Select the option that identifies the combination of all correct statements. 

QUESTION ID:15

The following table shows, forest floor litter pool and aboveground litterfall data for three forest types,

Based on the provided information, which one of the following options accurately identifies the various forest types? 

QUESTION ID:16

Urine volume is increased in osmotic diuresis which may be experimentally produced by the intravenous administration of mannitol that is filtered in the glomerulus but not reabsorbed in the renal tubule. The following statements suggest some of the physiological mechanisms of osmotic diuresis.

A. In the proximal tubule, water reabsorption falls due to presence of mannitol in tubular fluid and concentration of Na⁺ is diecreased in this fluid.

B. In the descending loop of Henle, reabsorption of water is increased as medullary hypertonicity is decreased in osmotic diuresis.

C. In the thin ascending loop of Henle, reabsorption of Na⁺ is increased as the concentration gradient for Na⁺ is decreased.

D. In the collecting duct, reabsorption of water is less because of decrease in osmotic gradient along the medullary pyramid in osmotic diuresis.

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

QUESTION ID:17

Cells have both reversible and non-reversible post-translational modifications. The following statements were made regarding the reversibility of post-translational modifications.

A. Ubiquitination of proteins is reversible, but ADP-ribosylation of DNA is irreversible.

B. Ubiquitination of proteins is reversible, but myristoylation of proteins is irreversible.

C. Ubiquitination of proteins is irreversible, but ADP-ribosylation of DNA is reversible.

D. Both ADP-ribosylation of DNA and prenylation of proteins are reversible.

E. Both prenylation and myristoylation of proteins are irreversible.

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

QUESTION ID:18

Following statements are made with respect to the production of transgenic plants.

A. Auxin can be used as a negative selection marker in plant transgenesis as it can be lethal to germinating seedlings at higher concentrations.

B. Agrobacterium inserts T-DNA at random locations in the plant genome and thus, it cannot be targeted to a desired location.

C. The antibiotic kanamycin interferes with the cytoplasmic ribosomal protein synthesis machinery, thereby acting as a positive selection marker.

D. Gene transfer by biolistic/particle gun bombardment usually results in lower transgene copy number and less DNA rearrangement than Agrobacteriummediated transformation.

Which one of the following options represents all INCORRECT statements?  

QUESTION ID:19

Given below are two columns depicting structural features (Column X) and the DNA/RNA conformation (Column Y).

Which one of the following options represents all correct matches between Column X and Column Y?  

QUESTION ID:20

A researcher uses taxon weighting and complementarity as criteria to prioritise communities for biodiversity conservation. The diagram below shows the distributions of five taxa (A to E) among four regions (R1 - R4). Column W represents the weightage given to these five taxa based on their taxonomic uniqueness.

Select the option that lists the appropriate order of regions that should be prioritised (from highest to lowest) for conservation.  

QUESTION ID:21

Match the animal in Column X with its characteristic in Column Y.

Which one of the following options represents all correct matches between Column X and Column Y? 

QUESTION ID:22

The table given below provides a comprehensive list of selected plant diseases (Column X) and possible causal pathogens (Column Y).

Which one of the following options represents all correct matches between Column X and Column Y?

QUESTION ID:23

Gradient formation of Fgf8 is governed by both diffusion from a localized source and removal of Fgf8 ligand through endocytosis. Both Rab5C and dynamin promote endocytosis. What would happen to the Fgf8 concentration gradient when Rab5C is overexpressed or dynamin is inhibited?

QUESTION ID:24

A purified 150 kDa protein species from gel filtration column was run on a 2- dimensional SOS-PAGE as shown below:

What is the likely form of the 150 kDa protein species from this observation?

QUESTION ID:25

A researcher simultaneously inhibited the activities of Traose-Phosphate Translocator (TPT) and Xylulose 5-Phosphate Translocator (XPT) in a plant and made the following assumptions:

A. Triose phosphate will be accumulated more in the chloroplast.

B. Triose phosphate will be accumulated more in the cytosol.

C. Xylulose 5-phosphate will be accumulated more in the chloroplast.

D. Xylulose 5-phosphate will be accumulated more in the cytosol.

Which one of the following combinations of the above assumptions is correct?  

QUESTION ID:26

RuBisCO enzyme catalyzes carboxylation or oxygenation of RuBP in five steps. Following are certain statements regarding the catalysis carried out by RuBisCO:

A. The first step of catalysis is enolization of RuBP.

B. The carbon-carbon bond between C3 and C4 of RuBP is cleaved.

C. Carboxylase activity produces only one molecule of 3-phosphoglycerate.

D. Oxygenase activity produces one molecule of 3-phosphoglycerate and one molecule of 2-phosphoglycolate.

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

QUESTION ID:27

Given below are different types of genetic manipulations of E. coli trp operon (Column X) and their consequences on its transcription (Column Y) under high tryptophan concentration.

 Which one of the following options represents all correct matches between Column X and Column Y?

QUESTION ID:28

The muscle spindles are the stretch receptors that initiate stretch reflex in skeletal muscles. The following statements are proposed to describe the structural and functional characteristics of the different components of a muscle spindle.

A. The specialized intrafusal fibers in muscle spindles have non-contractile polar ends and a contracrne centre.

B. The intrafusal fibers do not contribute to the overall contractile force of the muscle.

C. The primary sensory ending in a muscle spindle is formed by group la afferent fibers.

D. The axons of a-motor neurons having a diameter of 12-20 µm innervate the muscle spindles as the motor nerve.

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

QUESTION ID:29

Which one of the following is INCORRECT regarding Hill numbers ( q), a family of diversity indices?

QUESTION ID:30

A lac-lambda hybrid system is developed to study the λ-repressor protein. in which the λ Cl gene is under the control of E. coli lac promoter and operator, and the lacZ gene is under the control of λ-P_RM promoter and O_R operator of λ-phage. Both the plasmids are introduced in E. coli and the concentrations of the proteins are determined upon the addition of IPTG. 

QUESTION ID:31

Given below are a few statements about intracellular protein transport.

A. Proteins that are destined for the lysosome are tagged with a mannose-6- phosphate (M6P) group in the Golgi apparatus, which is recognized by the M6P receptor in the trans-Golgi network.

B. Signal recognition particle directly mediates the insertion of proteins into the mitochondrial membrane.

C. The KDEL receptor in the ER and Golgi apparatus works by retrieving soluble ER resident proteins that have accidentally moved to the Golgi.

D. Cargo proteins that need to be exported from the ER are packaged into COPII vesicles based on the presence of an ER export signal in their cytosolic tail.

E. Clathrin-coated vesi:cles are primarily involved in vesicle trafficking between the Golgi apparatus and the ER.

Choose the option that has all correct statements. 

QUESTION ID:32

Two newly identified proteins, X and Y, are tested for sequence-specific DNA binding activity. The results of an electrophoretic mobility shift assay (EMSA) with a labeled DNA fragment and proteins X and Yin various combinations are shown below.

Poly dl:dC is a DNA duplex of polyinosine and polycytosine. Which one of the following options represents the correct interpretation of the results obtained? 

QUESTION ID:33

In Drosophila melanogaster, a cross was performed, and the resulting progeny are indicated below.

The F₁ progeny were sib-mated and the F₂ progeny were analysed. The following statements were made based on the above crosses and analysis o·f the progeny:

A. The mutation leading to sepia eye color is located on an autosome.

B. Yellow body is a dominant phenotype.

C. One fourth of the F₂ progeny will be males with yellow body color.

D. In this dihybrid cross, as the F₂ progeny do not show a 9:3:3:1 typical Mendelian ratio, the two genes can be assumed to be linked.

Which one of the following options correctly identifies each statement as True (T) or False (F) from A to D, respectively?  

QUESTION ID:34

The statements given below describe an angiosperm flower.

A. A flower develops in the axils of bracts like axillary shoots.

B. The floral pedicel is the elongated node and the axis is condensed, like in a shoot.

C. Floral parts like calyx, corolla, androecium and gynoecium are modified leaves.

D. Floral buds may sometimes get modified into vegetative buds or bulbils.

Select the option with all correct statements that support the idea that a flower is a modified shoot. 

QUESTION ID:35

Quantitative Trait Loci (QTLs) can be identified using two main approaches: biparental matings (8PM) and Genome-Wide Association Studies (GWAS). Below are some descriptors related to these strategies:

A. Large sample size

B. Small sample size

C. Population derived from controlled crosses

D. Random mating populations

E. Limited to two alleles per locus

F. Multiple alleles per locus

G. Linkage-based mapping

H. Linkage disequilibrium-based mapping

The table below presents four incomplete statements regarding 8PM and GWAS. Each statement can be completed using the above descriptors. 

Which one of the following options correctly completes all statements? 

QUESTION ID:36

The insulin receptor is a receptor tyrosine kinase that engages the Pl3 kinase pathway to regulate a FOXO transcription factor. A student uses qRT-PCR to determine the expression of a direct FOXO target gene (GeneX) in a mammalian cell liine under different conditions and makes the following observations.

A. Treating the cells with a PTEN inhibitor irtcreases GeneX expression.

B. A cell line with an AKT (S308A) mutation !has increased GeneX expression.

C. Change in GeneX expression due to a ligand-binding defective insulin receptor is partly reversed by a PTEN inhibitor.

D. Phosphorylation of FOXO by PDK1 creates a phosphoserine binding site for 14-3-3 protein, reducing GeneX expression.

Which one of the following options represents all correct statements?

QUESTION ID:37

The following statements were made regarding regulation of aging in C. elegans:

A. In most cells, p53 remains bound to a repressor protein to keep it inactive, which is activated under oxidative stress when DNA damage separates p53 from its repressor.

B. DAF-2 functions as an insulin-like growth factor receptor to block Forkhead transcription factor and increases the life span.

C. When DAF-2 is not active, cells reduce the production of DNA repair enzymes.

D. Dietary restriction increases mTORC1 activity, enhancing functional stem cells and longevity.

Which one of the following options has the combination of all correct statements?

QUESTION ID:38

A parasitoid infects a host to complete its life cycle. Which of the following life-history traits typically characterizes this parasitoid, assuming that only one parasitoid infects one host?

QUESTION ID:39

Given below are the outcomes of transplantation experiments.

Which one of the following options correctly depicts the outcome of the transplantation experiments? 

QUESTION ID:40

The figure given below represents the same data in six different ways. "A" represents the scatter plot of all data points and "B" is its corresponding box and whisker plot. "C" to "F" represent the same dataset with different measures of central tendency alongside various measures of variation (SEM - Standard Error of Mean, SD - Standard Deviation, Cl - 95% confidence interval).

Which one of the following options is a correct representation of the data?  

QUESTION ID:41

At what range of substrate concentration will an enzyme with a k_cat of 30 s^-1 and a K_m of 0.005 M show one-quarter of its maximum rate?  

QUESTION ID:42

A student used four 20-mer oligos to amplify DNA (using a regular Taq DNA polymerase) from a wild type (WT), a homozygous mutant having a deletion of the gene (del), and from the heterozygous mutant (het), as shown in the figure below.

Agarose gel electrophoresis profiles:, using all four primers simultaneously, on each template are shown below. Which one of the options given below represents the correct profile?   

QUESTION ID:43

Given below are components that facilitate transfer of molecules across phospholipid bilayers (Column X) and the properties of these components (Column Y).

Choose the option that correctly matches the components with their properties. 

QUESTION ID:44

Protein X can be extracted from disrupted erythrocyte plasma membranes with high salt concentrations. Treatment of intact erythrocytes with protease followed by extraction led to intact protein X. Treatment of disrupted erythrocyte plasma membranes with protease followed by extraction led to fragmentedi protein X.

The following interpretations were made:

A. Protein X is a peripheral membrane protein

B. Protein X is an integral membrane protein

C. Protein X is on the extracellular matrix face of the plasma membrane

D. Protein X is on the cytosolic face of the plasma membrane

Which one of the following options best represents the combination of all correct interpretations?

QUESTION ID:45

Pollen tube growth in the transmission tract (TT) of the style and its attraction to the embryo sac are directed by chemical cues in plants, as discovered in Lily and Torenia. Which one of the following statements about the proteins/peptides secreted in the process is correct?

QUESTION ID:46

The following statements describe change in allele frequencies over time.

A. Fixation of an allele is purely by chance, while other alleles are lost.

B. Genetic drift can lead to the loss of certain alleles over time, reducing genetic diversity within the population.

C. Changes in allele frequencies are due to positive selection.

D. There is a pronounced effect in small populations, where random events can drastically alter allele frequencies.

Which one of the following options represents the combination of alI correct statements if allele frequencies change purely due to genetic drift? 

QUESTION ID:47

The table below gives the avian community composition of three communities (X, Y, Z), where '1' indicates the presence of the species in the community and ·0· indicates its absence.

Select the option that lists the correct order of similarity between pairs of communities based on Sorensen's coefficient of similarity. 

QUESTION ID:48

A researcher placed plant cells in a hypertonic solution to cause the cells to shrink. The following statements are made regarding the plasmolysed cells.

A. Microtubules are lost in the plasmolysed cells.

B. Protoplasts are retracted in the plasmolysed cells.

C. Hechtian strands are lost during plasmolysis.

D. Patches of plasma membrane remain affixed to the wall.

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

QUESTION ID:49

A researcher needs to identify if Protein A is localized in the ER in a human cell line. The cell has an RFP-tagged protein that marks the ER in this cell. Following are the proposed experiments.

A. Express Protein A fused to GFP at the N-terminus in the cells, followed by microscopy to check for colocalization with RFP.

B. Express Protein A fused to GFP at the C-terminus in the cells, followed by microscopy to check for colocalization with RFP.

C. lmmunofluorescence staining of A, followed by microscopy to check for colocalization with RFP.

D. Isolating the ER by differential centrifugation and checking for co-purification of Protein A with RFP.

Which one of the following options represents experiments that would most likely identify localization of Protein A in the ER?

QUESTION ID:50

The table below shows different developmental processes and associated signaling molecules/pathways.

Which one of the following options represents the correct association of developmental processes and signaling molecules?   

QUESTION ID:51

Actin dynamics in cells is dependent on several actin-binding proteins. Given below are actin-binding proteins in Column X and their typical function in Column Y.

Which one of the following options represents all correct matches between Column X and Column Y?

QUESTION ID:52

Men suffering from enlarged prostate disease were prescribed drugs that would specifically target the androgen receptor (AR). While developing the drug, the following considerations were deliberated on:

A. Drugs should target the N-terminal domain of the AR.

B. Drugs should not target the NLS domain of the AR.

C. The drug should bind to the ligand-binding domain of the AR.

D. The drug should activate CYP17A1 to facilitate conversion of pregnenolone to DHEA.

Which one of the following combinations of considerations will develop the best drug for tr,eatment of enlarged prostate? 

QUESTION ID:53

Synonymous mutations (solid black circle) and non-synonymous mutations (different symbols) are plotted on two hypothetical phylogenies (A and B) given below.

The phylogenies above may represent the following types of selection - positive, negative or neutral. Which one of the options given below gives the correct combination of the types of selection observed in phylogenies A and B?  

QUESTION ID:54

If a 0.1 M solution of glucose 1-phosphate is incubated with a catalytic amount of phosphoglucomutase, thie glucose 1-phosphate is transformed to glucose 6- phosphate. At equilibrium, the concentrations of the reaction components are:

              Glucose 1-phosphate ⇌ Glucose 6-phosphate

                   (4.5 x 10^-3 M)                   (9.6 x 10^-2 M) 

What would be the calculated values for K'_eq and ΔG⁰ ' for this reaction at 25°C?  

QUESTION ID:55

Which one of the following statements is NOT part of the neutral paradigm in ecology? 

QUESTION ID:56

The following statements are made regarding the role of cadherins in cell junctions.

A. Cadherins are calcium-dependent adhesion molecules that mediate cell to cell adhesion by forming homophilic interactions.

B. Cadherins function in tight junctions, sealing the space between adjacent cells.

C. N-cadherins are primarily found in epithelial cells and mediate adhesion to the basal lamina.

D. Cadherins are involved in the formation of focal adhesions, linking the cell cytoskeleton to the ECM.

E. Cadherins interact with the actin cytoskeleton through associated proteins like catenins.

Which one of the following options represents all correct statements?  

QUESTION ID:57

An enzyme has been found to efficiently catalyse the following reaction:

Where,    k_f : Forward rate of the reaction

                 k_r : Reverse rate of the reaction

                K_eq : Equilibrium Constant

Which one of the following parameters will be increased over the uncatalyzed reaction by the enzyme?   

QUESTION ID:58

The following statements describe a few basic features of the interferometric reflectance imaging sensor used as a biosensing platform:

A. This biosensing platform is capable of high-throughput multiplexing of proteinprotein, protein-DNA and DNA-DNA interactions.

B. The sensing surface is prepared by robotic spotting of biological probes that are immobilized on functionalised Si/SiO₂ substrate.

C. As biomass accumulates on the substrate surface, a change in the interferometric signature occurs and the change can be correlated to a quantifiable mass.

D. Using this technique, picometer changes in biomass may be detected.

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

QUESTION ID:59

Given below are a few statements regarding gene actions observed in plants.

A. In terms of pollination, self-pollinated species often exhibit additive gene action.

B. Non-additive gene action is less prevalent in cross-pollinated species.

C. Simply inherited (qualitative, oligogenic) traits predominantly exhibit nonadditive and epistatic gene action.

D. Genetic fixation of superior genes will be more difficult with dominance gene action.

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

QUESTION ID:60

A cytoplasmic monomeric protein containing a single non-surface exposed cysteine residue precipitates upon mutation of the Cys to 'lle'. However, the mutation of Cys to 'Ala' leads to a soluble and functional protein equivalent to the native form. Which one of the following statements explains the above observations? 

QUESTION ID:61

Given below are some statements regarding growth hormone (GH) secretion in humans.

A. Fasting increases GH secretion.

B. REM sleep decreases GH secretion.

C. Cortisol increases GH secretion.

D. Hypoglycemia decreases GH secretion.

Which one of the options given below represents both correct statements?  

QUESTION ID:62

In an experiment, FITC-CD4 and PE-CDS were used to stain thymocytes. The cells were then run through a flow cytometer and the data were plotted as CD4 vs CDS. The results are shown in the figure below and following statements are made: 

A. Rearrangement of TCR-13 locus is initiated in cells included in the quadrant containing 3.58% of tihe population.

B. TCR-a locus rearrangement occurs in cells included in the quadrant containing 87.5% population.

C. FITC-CD4 and PE-CDS cannot stain the same cells.

D. Rearranged TCR-y8 receptor is expressed on 7.06% population of cells.

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

QUESTION ID:63

The evolution of algal lineages is closely linked to endosymbiotic events. Which of the following statements best explains the origin and diversification of plastids in different algal groups?  

QUESTION ID:64

Lethally irradiated mice were split into 4 groups and experiments were conducted as described below:

Group 1 was not given any cells.

Group 2 was given thymus-derived cells from a syngeneic donor, and two months later. immunized with a polysaccharide antigen.

Group 3 was given bone marrow cells from a syngeneic donor, and two months later, immunized with a polysaccharide antigen.

Group 4 was given bone marrow cells from a syngeneic donor, and two months later, immunized with a T-dependent antigen.

Four possible outcomes, listed below, were suggested.

A. Group 1 mice are unlikely to survive.

B. Group 2 mice are likely to produce antibodies in response to polysaccharide antigens.

C. Group 3 mice are likely to produce antibodies in response to polysaccharide antigens.

D. Group 4 mice are likely to produce antabodies in response to T-dependent antigens.

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

QUESTION ID:65

The following statements were made regarding the roles of histone modifications in transcriptional regulation.

A. Acetylation of histones is generally associated with transcriptional repression by making the chromatin more compact.

B. Methylation of histones can either activate or repress transcription depending on the specific residue modified.

C. Phosphorylation of histones occurs in response to DNA damage and can influence gene expression.

D. Histone modifications influence the recruitment of RNA polymerase complex but not transcription factors.

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

QUESTION ID:66

Following statements are made regarding methyl erythritol phosphate (MEP) and mevalonate pathways for plant terpenoid biosynthesis.

A. The MEP pathway occurs in plastids whereas mevalonate pathway occurs in cytosol.

B. The mevalonate pathway supplies most of the Cs units of terpenoids for the biosynthesis of monoterpenes and diterpenes.

C. The MEP pathway supplies most of the Cs units of terpenoids ·for the biosynthesis of sesquiterpenes.

D. Certain genes of the plant MEP pathway are believed to have been acquired from the cyanobacterial symbiont.

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

QUESTION ID:67

The magnetic field generated from an electromagnet is used in the transcranial magnetic stimulation (TMS) of the brain. The following statements suggest some features of TMS:

A. The magnetic field generated in TMS induces an electrical field in the underlying brain area.

B. The electrical field in the brain area alters the membrane potential of the neurons in that locality causing them to depolarize synchronously, which in turn, may change the probability of the firing of neurons.

C. In cognitive neuroscience research, TMS may be used as a tool to induce a 'virtual lesion' in a selected region of the cerebral cortex.

D. TMS is safe and non-invasive but the neuronal activity of the stimulated area is disrupted for a long period of time.

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

QUESTION ID:68

The Marginal Value Theorem describes the behaviour of an animal foraging in a habitat where resources occur in patches. A major prediction of the theorem is how long an animal must stay in a patch to optimize the energy extracted, depending on its travel time to reach the patch, which is depicted in the figure below.

Based on this information, choose the option that correctly describes what both P and Q represent.