DUET 2021 Question Paper Ph.D In Biomedical Sciences

DU PhD In Biomedical Sciences
Topic:‐ BIOSCI PHD

1) Which among the following statements are true (T) or false (F) about the given reactions?

A. Acetoacetic ester synthesis intramolecular rearrangement leads to decarboxylation

B. Benzoin condensation an umpolung involves polarity inversion

C. Haloform synthesis is nucleophilic reaction to form chloroform

D. Perkin condensation is an aldol condensation to give a,b‐unsaturated aromatic compound

[Question ID = 5812]
1. A ‐ T, B ‐ T, C ‐ T, D ‐ T

[Option ID = 23245]
2. A ‐ F, B ‐ F, C ‐ T, D ‐ T

[Option ID = 23246]
3. A ‐ T, B ‐ F, C ‐ T, D ‐ F

[Option ID = 23247]
4. A ‐ T, B ‐ F, C ‐ T, D ‐ F

[Option ID = 23248]

2) Match List I with List II

List I List II
Name reaction Product obtained
A. Cannizzaro reaction I. Benzalacetophenone
B.Claisen‐Schmidt Reaction II. Substituted indole
C. Dieckmann condensation III. beta‐ketoester
D. Madelung reaction IV. Benzylalcohol and benzoic acid
Choose the correct answer from the options given below:

[Question ID = 5813]
1. A ‐ II, B ‐ I, C ‐ IV, D ‐ III [Option ID = 23249]
2. A ‐ II, B ‐ III, C ‐ IV, D ‐ I [Option ID = 23250]
3. A ‐ III, B ‐ I, C ‐ IV, D ‐ II [Option ID = 23251]
4. A ‐ IV, B ‐ I, C ‐ III, D ‐ II [Option ID = 23252]

3) Match List I with List II

List I List II
Compound Present Vitamin
A. ASCORBIC ACID I. VITAMIN B12
B.CYANOCOBALAMIN II. VITAMIN K
C. PHYLLOQUINONE III. VITAMIN B1
D. THIAMINE IV. VITAMIN C
[Question ID = 5814]
1. A ‐ II, B ‐ I, C ‐ IV, D ‐ III [Option ID = 23253]
2. A ‐ IV, B ‐ III, C ‐ II, D ‐ I [Option ID = 23254]
3. A ‐ IV, B ‐ I, C ‐ II, D ‐ III [Option ID = 23255]
4. A ‐ III, B ‐ I, C ‐ IV, D ‐ II [Option ID = 23256]

4) Identify the true (T) or false (F) in the following statements on protein conformation:

A. Dihedral angles of side‐chains in amino acids are depicted in the Ramachandran plot.

B. Infrared spectroscopy can be used to deduce H‐bonding in peptides.

C. 3D structures of protein composed of approximately 100 amino acids can be obtained by NMR spectroscopy.

D. Globular proteins have α ‐helical and β‐sheet components

[Question ID = 5815]
1. A ‐ F, B ‐ T, C ‐ T, D ‐ T

[Option ID = 23257]
2. A ‐ T, B ‐ T, C ‐ T, D ‐ F

[Option ID = 23258]
3. A ‐ T, B ‐ T, C ‐ F, D ‐ F

[Option ID = 23259]
4. A ‐ F, B ‐ T, C ‐ F, D ‐ T

[Option ID = 23260]

5)

[Question ID = 5816]
1. Cyclopropylmethyl > Benzyl> tert‐butyl, because s character at the carbanionic carbon decreases

[Option ID = 23261]
2. Cyclopropylmethyl > Benzyl> tert‐butyl, because s character at the carbanionic carbon increases

[Option ID = 23262]
3. Cyclopropylmethyl <Benzyl<tert‐butyl,because s character at the carbanioniccarben decreases

[Option ID = 23263]
4. Cyclopropylmethyl<Bnzyl< tert‐butyl,because s character at the carbanionic carbon increases

[Option ID = 23264]

6) Which one of the following is NOT CORRECT about Mannich reaction?

[Question ID = 5817]
1. Reactions between aldimines and α‐methylene carbonyls

[Option ID = 23265]
2. Amino alkylation of an α‐methylene carbonyls with formaldehyde and ammonia

[Option ID = 23266]
3. Formation of β‐amino‐carbonyl compound

[Option ID = 23267]
4. Reactions between aldehyde and carbonyls

[Option ID = 23268]

7)

[Question ID = 5818]
1. 1(S); 2(S)

[Option ID = 23269]
2. 1(S); 2(R)

[Option ID = 23270]
3. 1(R); 2(S)

[Option ID = 23271]
4. 1(R); 2(R)

[Option ID = 23272]

8) The oxidation state of carbons (CH3 and COOH) in acetic acid are

[Question ID = 5819]
1. +3, +3 [Option ID = 23273]
2. +4, +4 [Option ID = 23274]
3. ‐3, +3 [Option ID = 23275]
4. +4, ‐4 [Option ID = 23276]

9) The optical purity of a substance can be measured by comparing the optical rotation of the sample to the known optical
rotation of a single entantiomer of that compound. Optical purity is usually measured in percent enantiomeric excess (%ee).

(R)‐2‐bromobutane has a specific rotation of ‐23.1o . A mixture of the 2‐bromobutanes of measured specific rotation = ‐9.2o ,
where the enantiomeric excess is given by ee=observed specific rotation/ maximum specific rotation×100%

What is the percentage of R and S enantiomers in the mixture?

[Question ID = 5820]
1. 60/40

[Option ID = 23277]
2. 70/30

[Option ID = 23278]
3. 80/20

[Option ID = 23279]
4. 90/10

[Option ID = 23280]

10) Ibuprofen belongs to nonsteroidal anti‐inflammatory drug (NSAID) class that is used for treating pain, fever,
and inflammation, the active compound possesses (S) stereochemistry, which among the following structure has a
stereochemistry to denote Ibuprofen:

[Question ID = 5821]
1. I (R configuration) [Option ID = 23281]
2. II (S configuration) [Option ID = 23282]
3. III (RS configuration) [Option ID = 23283]
4. All of the above [Option ID = 23284]

11) DNA melting temperature (Tm) was found to be 470C and enthalpy measured at Tm was 0.032kJ. Entropy =
Enthalpy/Tm, where T (Kelvin). What will be the entropy change?[Question ID = 5822]
1. 1 X 10‐3 kJ [Option ID = 23285]
2. 1 X 10‐4 kJ [Option ID = 23286]
3. 3 X 10‐2 kJ [Option ID = 23287]
4. 6 x 10‐2 kJ [Option ID = 23288]

12) When natural cholesterol 0.300 g is dissolved in chloroform (15 ml) and is placed in a10 cm polarimeter tube, the
observed rotation at 200C (using the D line of sodium) is ‐0.6300. Given [α] = αobs/c (g/ml) x l (dm). The specific rotation of
cholesterol is

[Question ID = 5823]
1. ‐27.5

[Option ID = 23289]
2. ‐31.5

[Option ID = 23290]
3. ‐35.5

[Option ID = 23291]
4. ‐39.5

[Option ID = 23292]

13) A mixture of anthracene, acetophenone and β‐naphthol was analyzed on thin layer chromatography using
hexane/ethylacetate (10:2) as mobile phase with rf values 0.7, 0.5, and 0.3 respectively, the same mixture was separated
on HPLC column (Reverse phase C18) in one of the following mobile phase:[Question ID = 5824]
1. Hexane/ethylacetate (10:1) [Option ID = 23293]
2. Hexane /methanol (10:1) [Option ID = 23294]
3. Hexane /ethanol (10:1) [Option ID = 23295]
4. Acetonitrile/water(10:1) [Option ID = 23296]

14) Number of signals in the 13C [1H] NMR spectrum of Ethanol are:[Question ID = 5825]
1. 3 [Option ID = 23297]
2. 4 [Option ID = 23298]
3. 5 [Option ID = 23299]
4. 6 [Option ID = 23300]

15) Theoretical plates are used to[Question ID = 5826]
1. Estimate the efficiency of a column [Option ID = 23301]
2. Determine the thickness of the stationary phase [Option ID = 23302]
3. Measure the distribution of the analyte between mobile and stationary phases [Option ID = 23303]

4. None of the above [Option ID = 23304]

16) Wang resin is one of the standard peptide synthesis resin used with Fmoc (fluorenylmethoxycarbonyl chloride)
chemistry, the structure of the resin is represented as:[Question ID = 5827]
1. 2‐alkyl‐benzyl alcohol functionalized polyvinyl [Option ID = 23305]
2. 2‐alkyl‐benzyl alcohol functionalized polystyrene [Option ID = 23306]
3. 4‐alkyl‐benzyl alcohol functionalized polyvinyl [Option ID = 23307]
4. 4‐alkoxybenzyl alcohol functionalized polystyrene [Option ID = 23308]

17) Which is the CORRECT decreasing order of pKa of the following compounds?

i) CHF2COOH ii) CH3COOH iii) CH2FCOOH iv) CH2ClCOOH

[Question ID = 5828]
1. i, ii, iii, iv

[Option ID = 23309]
2. ii, iv, iii, i

[Option ID = 23310]
3. iii, iv, i, ii

[Option ID = 23311]
4. iv, i, ii, iii

[Option ID = 23312]

18) Which one of the following statements on protein conformation is CORRECT?

[Question ID = 5829]
1. The dihedral angles phi, psi of amino acids in unfolded proteins are exclusively positive

[Option ID = 23313]
2. A peptide rich in proline is likely to adopt alpha helical structure

[Option ID = 23314]
3. A peptide rich in proline is likely to adopt beta turns

[Option ID = 23315]
4. L‐amino acids are unable to adopt beta turns when both phi, psi are positive

[Option ID = 23316]

19) The presence of D‐amino acids in the crosslinks of the peptidoglycan layer is most likely because[Question ID = 5830]
1. Most peptidases can only cleave L‐amino acids [Option ID = 23317]
2. D‐amino acids fit the structural constrains of the cell wall better than L‐amino acids [Option ID = 23318]
3. Most L‐amino acids have already been used for protein synthesis [Option ID = 23319]
4. D‐amino acids are easier to crosslink in the absence of ribosomes [Option ID = 23320]

20) A prodrug is a medication or compound that, after administration, is metabolized (i.e., converted within the body) into
a pharmacologically active drug. Which of the following is NOT a prodrug?[Question ID = 5831]
1. Levodopa [Option ID = 23321]
2. Enalaprilmaleate [Option ID = 23322]
3. Proparacetamol [Option ID = 23323]
4. Ampicillin [Option ID = 23324]

21) Which one of the following statements correctly represent the eudismic ratio?[Question ID = 5832]
1. Difference in the pharmacokinetics of drugs [Option ID = 23325]
2. Potency of eutomer relative to that of the distomer [Option ID = 23326]
3. Isomeric ballast relative to eutomer [Option ID = 23327]
4. Isomeric ballast relative to distomer [Option ID = 23328]

22) A nitrogen mustard medication used for chemotherapy is able to form inter‐strand crosslinks in DNA, which prevents
DNA replication and DNA transcription. Identify the nitrogen mustard medication from the following [Question ID = 5833]
1. Bleomycin [Option ID = 23329]
2. Carmustine [Option ID = 23330]
3. Ethidium bromide [Option ID = 23331]
4. Hoechst [Option ID = 23332]

23) In pharmacology, potency is a measure of drug activity expressed in terms of the amount required to produce an effect
of given intensity. The potency of a drug depends on[Question ID = 5834]
1. The affinity to bind to a receptor [Option ID = 23333]
2. The efficacy to initiate a response [Option ID = 23334]
3. Both a and b [Option ID = 23335]
4. Severity of disease [Option ID = 23336]

24) A regulated course of doses of a therapeutic agent including the time between doses or the time when the dose
(s) are to be given at each specific time intended to preserve or restore health is called[Question ID = 5835]
1. Regimen [Option ID = 23337]

2. Therapeutic observation [Option ID = 23338]
3. Health Monitoring [Option ID = 23339]
4. Therapeutic index [Option ID = 23340]

25) GABAA receptors are the target for attenuating the various CNS disorders, which one of the following drugs DOES NOT
mediate the action through GABA receptors?[Question ID = 5836]
1. Vigabatrin [Option ID = 23341]
2. Librium [Option ID = 23342]
3. Enalapril [Option ID = 23343]
4. Phenobarbital [Option ID = 23344]

26) Pupillary muscle groups are controlled by the Autonomic nervous system. Which of the following statements are true
(T) or False (F)?

A. Parasympathetic activation causes pupillary constriction

B. Parasympathetic activation causes pupillary dilation

C. Sympathetic activation causes pupillary dilation.

D. Sympathetic activation causes pupillary dilation.

[Question ID = 5837]
1. A ‐ T, B ‐ T, C ‐ F, D ‐ T

[Option ID = 23345]
2. A ‐ F, B ‐ F, C ‐ T, D ‐ T

[Option ID = 23346]
3. A ‐ T, B ‐ F, C ‐ T, D ‐ F

[Option ID = 23347]
4. A ‐ F, B ‐ T, C ‐ F, D ‐ T

[Option ID = 23348]

27) Which one of the following is the rate determining step in glycolysis?

[Question ID = 5838]
1. Conversion of glucose to glucose‐6‐phosphate

[Option ID = 23349]
2. Conversion of fructose‐6‐phosphate to fructose‐1,6‐bisphosphate

[Option ID = 23350]
3. Conversion of glyceraldehydes‐3‐phosphate to 1‐3‐bisphosphoglycerate

[Option ID = 23351]
4. Conversion of 3‐phosphoglycerate to 2‐phosphoglycerate

[Option ID = 23352]

28) Human olfactory receptors are:

[Question ID = 5839]
1. Ionotropic receptors

[Option ID = 23353]
2. G‐protein coupled receptors

[Option ID = 23354]
3. Thermoreceptors

[Option ID = 23355]
4. Fc receptors

[Option ID = 23356]

29) In Southern hybridization:

[Question ID = 5840]
1. DNA is fractionated & probed with labeled oligonucleotides

[Option ID = 23357]
2. RNA is fractionated & probed with labeled oligonucleotides

[Option ID = 23358]
3. Protein is fractionated & probed with labeled oligonucleotides

[Option ID = 23359]
4. Protein is fractionated &probed with antibody

[Option ID = 23360]

30) State whether the following statement is true (T) or false(F) about the complex metal carrying ring system in vitamin
B12:

A. Has a corrin ring system

B. Has a cobalt metal in pentacoordinate state

C. Has a cobalt metal in hexacoordinate state

D. Ring is chemically related to porphyrin​

[Question ID = 5841]
1. A ‐ T, B ‐ T, C ‐ F, D ‐ T

[Option ID = 23361]
2. A ‐ T, B ‐ T, C ‐ T, D ‐ F

[Option ID = 23362]
3. A ‐ T, B ‐ F, C ‐ T, D ‐ F

[Option ID = 23363]
4. A ‐ F, B ‐ T, C ‐ T, D ‐ F

[Option ID = 23364]

31) The frequency of a perceived sound depends on:

[Question ID = 5842]
1. The frequency of stereocilia vibration.

[Option ID = 23365]
2. The number of hair cells that are stimulated.

[Option ID = 23366]
3. Region of the cochlear duct is stimulated.

[Option ID = 23367]
4. The movement of perilymph in the cochlear duct.

[Option ID = 23368]

32) Polysomnographic recording consists of all except:

[Question ID = 5843]
1. EEG

[Option ID = 23369]
2. ECG

[Option ID = 23370]
3. EOG

[Option ID = 23371]
4. EMG

[Option ID = 23372]

33) Rigor mortis occurs in a dead person because:

[Question ID = 5844]
1. ATP, which is necessary for the detachment of cross bridges, is not being formed

[Option ID = 23373]
2. ATP, which is necessary for the formation of cross bridges, is not being formed

[Option ID = 23374]
3. Deterioration of muscle proteins prevents detachment of cross bridges

[Option ID = 23375]
4. ATP continues to be formed for several hours after death

[Option ID = 23376]

34) Emphysema is characterized by:

[Question ID = 5845]
1. Loss of peripheral vision

[Option ID = 23377]
2. Shortness of breath

[Option ID = 23378]
3. Chronic Diarrhea

[Option ID = 23379]
4. Slow clotting from wounds

[Option ID = 23380]

35) Resolving power of a light microscope is a function of:

[Question ID = 5846]
1. Wavelength of light used

[Option ID = 23381]
2. Numerical aperture of lens system

[Option ID = 23382]
3. Thermal index

[Option ID = 23383]
4. Both 1 and 2

[Option ID = 23384]

36) In a cloning experiment, alkaline phosphatase is generally used to dephosphorylate a plasmid vector rather than the
insert DNA fragments because:[Question ID = 5847]
1. Alkaline phosphatase can only dephosphorylate plasmid vector and not insert DNA fragments [Option ID = 23385]
2. Vector can self‐ligate and form colonies upon introduction into host cells [Option ID = 23386]
3. Insert DNA fragments can self‐ligate and form colonies upon introduction into host cells [Option ID = 23387]
4. Vector cannot ligate to a dephosphorylated insert DNA fragment [Option ID = 23388]

37) Which of the following plasma membrane receptors activate signaling pathways usually by forming molecular dimers
that result in protein phosphorylation reactions upon binding of their specific ligand?[Question ID = 5848]
1. Steroid hormone receptors [Option ID = 23389]
2. Receptor tyrosine kinases [Option ID = 23390]
3. Ligand‐gated ion channels [Option ID = 23391]
4. G protein‐coupled receptors [Option ID = 23392]

38) RPM1‐1640 and DMEM are routinely used:[Question ID = 5849]
1. Bacterial culture media [Option ID = 23393]
2. Mammalian cell culture media [Option ID = 23394]
3. Antibiotic resistant strains of HINI virus [Option ID = 23395]
4. Newly identified Mycobacterial strains [Option ID = 23396]

39) Recently USFDA approved CAR‐T treatment is a: [Question ID = 5850]
1. Monoclonal antibody therapy [Option ID = 23397]
2. Cell based therapy [Option ID = 23398]
3. Small molecule therapy [Option ID = 23399]
4. Photoactive agent based therapy [Option ID = 23400]

40) Match List I with List II

List I List II
Molecules Mechanism of actions

A. Bradykinin I. ​Lipid mediators that play pivotal roles in acute and chronic inflammation and allergic diseases
II. ​Long‐chain fatty acids involved in activation of the inflammatory response, production of
B. Leukotrienes
pain, and fever.
III. ​An organic nitrogenous compound involved in allergic immune responses, also acting as a
C. Prostaglandins
neurotransmitter
D. Histamine IV. ​A potent endothelium‐dependent vasodilator peptide, lowers blood pressure
Choose the CORRECT answer from the options given below:

[Question ID = 5851]
1. A ‐ II, B ‐ I, C ‐ IV, D ‐ III [Option ID = 23401]
2. A ‐ I, B ‐ II, C ‐ III, D ‐ IV [Option ID = 23402]
3. A ‐ IV, B ‐ I, C ‐ II, D ‐ III [Option ID = 23403]
4. A ‐ III, B ‐ IV, C ‐ II, D ‐ I [Option ID = 23404]

41) The corona virus consists of: [Question ID = 5852]
1. 14 non‐structural and 6 structural proteins [Option ID = 23405]
2. 18 non‐structural and 4 structural proteins [Option ID = 23406]
3. 16 non‐structural and 4 structural proteins [Option ID = 23407]
4. 14 non‐structural and 8 structural proteins [Option ID = 23408]

42) Automated DNA sequencing is an improvement of Sanger’s method where: [Question ID = 5853]
1. Unlabeled ddNTPs are used for chain termination [Option ID = 23409]
2. Fluorescently labeled ddNTPs are used for chain termination [Option ID = 23410]
3. Unlabeled dNTPs are used for chain termination [Option ID = 23411]
4. Fluorescently labeled dNTPs are used for chain termination [Option ID = 23412]

43) In which cancer treatment erb‐B antibodies are used:[Question ID = 5854]
1. Breast [Option ID = 23413]
2. Oral [Option ID = 23414]
3. Lung [Option ID = 23415]

4. Prostrate [Option ID = 23416]

44) The biological activity of endotoxin in gram‐negative bacteria is associated with:[Question ID = 5855]
1. Steroids [Option ID = 23417]
2. Peptidoglycans [Option ID = 23418]
3. Lipopolysaccharides [Option ID = 23419]
4. Polypeptides [Option ID = 23420]

45) Identify the INCORRECT statement about SARS‐CoV‐2 virus:

[Question ID = 5856]
1. It is an RNA virus.

[Option ID = 23421]
2. It is a DNA virus.

[Option ID = 23422]
3. It is highly mutation prone.

[Option ID = 23423]
4. Neutralizing vaccines are available against SARS‐CoV‐2 infection.

[Option ID = 23424]

46) Delta virus variant of Coronavirus from India contains following mutations in the spike protein:[Question ID = 5857]
1. E484D and L425A [Option ID = 23425]
2. E484M and L425E [Option ID = 23426]
3. E484Q and L425R [Option ID = 23427]
4. E484 R and L425A [Option ID = 23428]

47) Two siblings who inherit 50% of the genome from the mother and 50% from the father show a lot of phenotypic
differences. Which one of the following events during gametogenesis of the parents will maximally contribute to this
difference?[Question ID = 5858]
1. Mutation [Option ID = 23429]
2. Recombination [Option ID = 23430]
3. Independent assortment [Option ID = 23431]
4. Environment [Option ID = 23432]

48) The inheritance of a given disorder is recorded in three small family as shown below:

Based on the above limited information, which one of the following inheritance pattern best explains the observations?

[Question ID = 5859]
1. X‐linked recessive

[Option ID = 23433]
2. X‐linked dominant

[Option ID = 23434]
3. Autosomal recessive

[Option ID = 23435]
4. Autosomal dominant

[Option ID = 23436]

49) Mutation in gene ‘X’ leads to lethality in a haploid organism. Which one of the following is best suited to analyse the
function of gene ‘X’?[Question ID = 5860]
1. Pleiotropic mutants [Option ID = 23437]
2. Temperature‐sensitive mutants [Option ID = 23438]
3. Recessive mutants [Option ID = 23439]
4. Mutants with low penetrance [Option ID = 23440]

50) Action of parathyroid hormone in the human body: [Question ID = 5861]
1. Decreases blood sodium level [Option ID = 23441]
2. Increases blood sodium level [Option ID = 23442]
3. Decreases blood calcium level [Option ID = 23443]
4. Increases blood calcium level [Option ID = 23444]