Which one of the following statements is correct about proportional controllers?

Which of the following techniques is best suited for immobilizing an affinity ligand?

A. Physical adsorption

B. Gel entrapment

C. Crosslinking with a polymer

D. Covalent linkage to a spacer arm

Which one of the following can not be a limiting substrate if Monod's growth kinetics is applicable?

A. Extracellular carbon source

B. Extracellular nitrogen source

C. Dissolved oxygen

D. Intracellular carbon source

During cultivation of microorganisms in a fermenter, various parameters are controlled by appropriate sensor (probe). Match each probe in Group I with the appropriate response mechanism in Group II.

A. P-2, Q-3, R-1, S-4

B. P-1, Q-2, R-4, S-3

C. P-3, Q-2, R-4, S-1

D. P-3, Q-4, R-2, S-1

The kinetics of the disintegration of baker's yeast cells in a bead mill is described as $$\frac{{dp}}{{dt}} = K\left( {{P_m} - P} \right)$$   , where P is the concentration of protein released, m is the maximum protein concentration achievable, K is the first order rate constant and is 0.5 h⁻¹ for the system studied. The time required for the release of 90% of the intracellular proteins will be:

A. 10 h

B. 0.2 h

C. 4.6 h

D. None of the above