Indicate the INCORRECT statement from the following:

• Allosteric enzymes function through reversible noncovalent binding of allosteric modulators or effectors.

• Monoclonal antibodies that catalyze the hydrolysis of esters or carbonates can be produced.

• Enzymes are not inhibited irreversibly by heavy metals such as Hg²⁺, Ag⁺.

• Acid phosphates hydrolyze biological phosphate esters at ∼ pH 5.0

What is the effect of sudden increase in the levels of ATP and citrate on an erythrocyte undergoing glycolysis?

• It inhibits glycolysis.

• It stimulates glycolysis.

• The rate of glycolysis remains unaltered.

• The rate of glycolysis increases gradually.

The φ and ψ of a β-strand composed of all D-amino acids will mainly occupy which quadrant in the Ramachandran plot?

• upper left

• upper right

• lower left

• lower right

The following observations are made regarding a peptide sequence.

- The peptide is inert to Ellman's reagent. However, on reacting with β-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?

• It is an α-helical peptide that undergoes aggregation.

• It is an α-helical disulfide bridged peptide that undergoes aggregation.

• It is an β-hairpin peptide, which is stabilized by a disulfide bridge.

• The peptide is composed of an α-helical and β-sheet connected by a disulfide bridge.

Which one of the following statements regarding proteins is CORRECT?

• n → σ* transition requires less energy than n → $\mathrm{\pi }$* transition and can e monitored by mass spectrometry.

• n → $\mathrm{\pi }$* transition requires more energy than $\mathrm{\pi } \to \mathrm{\pi }$* transition and can be monitored by UV-Vis spectroscopy.

• n → $\mathrm{\pi }$* transition requires less energy than n → σ* transition and can be monitored by CD spectroscopy.

• σ → σ* transition requires less energy than n → $\mathrm{\pi }$* transition and can be monitored by CD spectroscopy.

Match the coenzymes in column I serving as transient carriers of specific atoms or functional groups in column II.

Column I	Column II
A. Coenzyme A	i. Aldehyde groups
B. Flavin adenine dinucleotide	ii. Amino groups
C. Pyridoxal phosphate	iii. Hydrogen
D. Thiamine pyrophosphate	iv. Acyl groups

Select correct combinations from the options given below:

• A - iv; B - iii; C - ii; D - i

• A - iii; B - iv; C - i; D - ii

• A - i; B - ii; C - iii; D - iv

• A - ii; B - i; C - iv; D - iii

Out of the statements mentioned below:

A. L-threonine and L-allo-threonine interact identically with plane polarized light.

B. van der Waals' interactions are always attractive.

C. Poly (pro) II-helix is not stabilized by intermolecular hydrogen bonds.

D. The folding of a protein is associated with an overall positive change in free energy and negative change in entropy.

E. Lysine acetylation on histone is associated with loosening of the histone complex from DNA.

Which of the following combinations is CORRECT?

• A and C

• B and D

• C and E

• D and E

The following statements are made:

A. α and βanomers of glucose are inter-convertible and the ratio of their abundance is 1 : 2, respectively.

B. Single chain lipids (≥C₁₄) form micelles and double chain lipids form bilayers in water,.

C. Proline is energetically favoured at the C- termini of an α-helix than at the N-termini.

D. Major groove of DNA readily accommodates several common structural motifs in protein than the minor groove.

E. Replacement of a canonical Watson-Crick pairing by Wobble base pairs does not change the surface properties in t-RNA.

Which one of the following combinations is INCORRECT?

• A and D

• B and E

• C and E

• B and C

From the following statements,

A. Enzymes enhance reaction rates by a factor of 2 to 10.

B. The activation energy for a reaction is lowered by enzymes.

C. The interactions between enzymes and substrates are hydrogen bonding, hydrophobic and ionic.

D. Substrate concentration does not affect the rate of enzyme catalyzed reactions.

Pick the combination with all INCORRECT statements.

• A, B

• B, C

• A, C

• A, D

Match the chemical agents that interfere in oxidative phosphorylation process with their respective mode of action.

Column I	Column II
A. Antimycin A	i. Inhibits Fo component of ATP synthase.
B. Oligomycin	ii. Disrupts inner mitochondrial membrane potential.
C. Valinomycin	iii. Prevent electron transport from Fe/ S cluster to ubiquinone.
D. Rotenone	iv. Blocks electron transfer from cytochrome b to cytochrome c1.
	v. Inhibits adenine nucleotide translocase.

Choose the correct combination from below:

• A - ii; B - iv; C - v; D - iii

• A - iv; B -i; C - ii; D - iii

• A - i; B - iii; C - ii; D - v

• A- v; B - ii; C - i; D - ii