Which one or more of the following statements correctly describe(s) fluorescence spectroscopy?

(A) The emission maxima (λmax) is independent of the excitation wavelength.
(B) The emission maxima (λmax) depends on the concentration of a quencher.
(C) The emission maxima (λmax) varies with solvent polarity.
(D) The emission maxima (λmax) varies with temperature.

Which one or more of the following statements is/are correct regarding the transport and retention of proteins in different cell organelles?

(A) Mannose 6-phosphate residues are involved in targeting proteins to lysosomes.
(B) Transport of proteins into the mitochondrial compartment is aided by positively charged amino acid residues at the N-terminus and internal hydrophobic segments.
(C) The retention of protein in the ER lumen requires the KDEL sequence motif at the C-terminus.
(D) Nuclear proteins are transported in an unfolded conformation and the nuclear localization signal sequence is subsequently cleaved by peptidases in the nucleoplasm.

Which one or more of the following statements is/are correct regarding the electromotive force generated by the electron transfer chain?

(A) It is used for the synthesis of ATP.
(B) It is not used for active transport processes.
(C) It includes a pH gradient component.
(D) It does not include an electrical potential gradient component.

Which one of the following is the correct match between the molecular properties listed in Column I and the corresponding biochemical separation methods in Column II?

(A) P-i; Q-ii; R-v; S-iii
(B) P-iii; Q-iv; R-ii; S-i
(C) P-iii; Q-iv; R-i; S-ii
(D) P-v; Q-iv; R-iii; S-ii

Metabolic intermediates provide the backbone for the synthesis of amino acids. Match the metabolic intermediates listed in Column I with their corresponding amino acids given in Column II.

(A) P-ii; Q-i; R-v; S-iv
(B) P-iii; Q-ii; R-i; S-v
(C) P-iv; Q-iii; R-ii; S-v
(D) P-ii; Q-i; R-iv; S-v

If a 10 mM solution of a biomolecule in a cuvette of path length 10 mm absorbs 90% of the incident light at 280 nm, the molar extinction coefficient of the biomolecule at this wavelength is _____________ M⁻¹cm⁻¹.

In a lactic acid solution at pH 4.8, the concentrations of lactic acid and lactate are 0.01 M and 0.087 M, respectively. The calculated pKa of lactic acid is ________.

A newly identified viral protein contains one long α-helix spanning 60 amino acid residues. The number of main chain H-bonds formed in this helix is __________.

Which one or more of the following statements correctly describe(s) the addition of N-nucleotides during the rearrangement of the immunoglobulin heavy chain-encoding gene?

(A) Addition of N-nucleotides is template encoded.
(B) N-nucleotides are added by terminal deoxynucleotidyl transferase.
(C) The added N-nucleotides are common in V-D and D-J junction.
(D) N-nucleotides are added by the DNA polymerase II.

In mammals, hematopoietic stem cells that give rise to different types of blood cells are known as

(A) totipotent stem cells.
(B) pluripotent stem cells.
(C) myeloid progenitor cells.
(D) lymphoid progenitor cells.