Which of the following does NOT describe a mechanism that cells use to regulate enzyme activities?

A. Cells control enzyme activity by phosphorylation and dephosphorylation.

B. Cells control enzyme activity by the binding of small molecules.

C. Cells control the rates of diffusion of substrates to enzymes.

D. Cells control the rates of enzyme degradation.

E. Cells control the rates of enzyme synthesis.

F. Cells control the targeting of enzymes to specific organelles. 

#Question id: 14649

#Section 1: Engineering Mathematics

The n^th non zero term of Maclaurin series for ln (1 + x² ) is

#Question id: 105

#Section 2: General Biology

Isoprenoids are lipids which neither contain nor are derived from fatty acids and include

A) steroids.

B) waxes.

C) terpenes.

#Question id: 27431

#Section 5: Bioprocess Engineering and Process Biotechnology

The immobilization technique which may be accomplished without the solid matrix, is

#Question id: 19483

#Section 4: Fundamentals of Biological Engineering

#Question id: 14200

#Section 5: Bioprocess Engineering and Process Biotechnology

A fluidized-bed, immobilized-cell bioreactor is used for the conversion of glucose to ethanol by Z. mobilis cells immobilized in k-carrageenan gel beads. The dimensions of the bed are 10 cm (diameter) by 200 cm. Since the reactor is fed from the bottom of the column and because of CO₂ gas evolution, substrate and cell concentrations decrease with the height of the column. The average cell concentration at the bottom of the column is X₀ = 45 g/l, and the average cell concentration decreases with the column height according to the following equation:

where Z is the column height (cm). The specific rate of substrate consumption is q_S = 2 g S/g cells . h. The feed flow rate and glucose concentration in the feed are 5 l/h and 160 g glucose/l, respectively.

Determine the ethanol concentration in the effluent (g/l . h) if YP/S = 0.48 g ethanol/g glucose