Bioprocess Engineering and Process Biotechnology MCQs

Which of the following factors can influence the lag phase of a microbial culture in a batch fermenter? P. Inoculum size Q. Inoculum age R. Medium composition

Since mammalian cells are sensitive to shear, scale-up of a mammalian cell process must consider, among other parameters, the following (given, N = rotations/time, D = diameter of impeller)

Match the properties in Group I with the downstream operations in Group II. Group I Group II P. Size 1. Extraction Q. Density 2. Distillation R. Volatility 3. Filtration S. Solubility 4. Sedimentation

The diameters of a large and a small vessel are 1.62 m and 16.2 cm, respectively. The vessels are geometrically similar and operated under similar volumetric agitated power input. The mixing time in the small vessel was found to be 15 s. Determine the mixing time (in seconds) in the large vessel.

Which one of the following is catabolized during endogenous metabolism in a batch bacterial cultivation?

Which of the following statements are true about bioreactors? P. Continuous bioreactors provide less degree of control and uniform product quality than batch bioreactors. Q. Batch bioreactors are ideally suited for reaction with substrate inhibition. R. Choice of a bioreactor is dictated by kinetic considerations. S. Fed batch bioreactors are also called semi-batch bioreactors.

Which of the following statements is always correct about an ideal chemostat? P. Substrate concentration inside the chemostat is equal to that in the exit stream. Q. Optimal dilution rate is lower than critical dilution rate. R. Biomass concentration increases with increase in dilution rate. S. Cell recirculation facilitates operation beyond critical dilution rate.

Which of the following statements applies to the operation of a fed-batch process?

Wash out (as defined by D = μmax) of a continuous stirred tank fermenter is characterized by (X = biomass, S = substrate concentration in bioreactor, S0 = substrate concentration in feed, P = product concentration in bioreactor).