Which of the following statements are correct? Very long DNA fragments (> 100 kb) from eukaryotic genomes
P. Can be efficiency packaged in a λ phage vector
Q. Can be propagated in yeast artificial chromosomes
R. Must have cohesive ends for cloning
S. Can be separated by pulsed field gel electrophoresis techniques

Which of the following is a prime example of a ribonucleoprotein enzyme, the catalytic activity of which (under non-physiological conditions), resides solely in its RNA component

A. Reverse transcriptase

B. Cytochrome c

C. Bacterial RNA polymerase

D. RNase P

Main functions of baffles in a bioreactor are
P. To prevent a vortex.
Q. To increase aeration.
R. To reduce interfacial area of oxygen transfer.
S. To reduce aeration rate.

A. P, Q

B. Q, R

C. R, S

D. P, S

All the following may be methods for the inhibition of microbial growth by antibiotics except

A. Antibiotics disrupt cell wall synthesis

B. Antibiotics interfere with cell membrane function

C. Antibiotics prevent the release of energy from ATP

D. Antibiotics inhibit the synthesis of protein

A feature common to almost all transmembrane proteins is

A. A phosphorylated exterior domain

B. A structure consisting almost exclusively of beta-sheets

C. An amino acid sequence rich in acidic residues

D. An alpha-helical region of about 20 to 25 hydrophobic amino acids