16. Which of the following event occurs during the second phase of the growth of P. chrysogenum?

A. Synthesis of penicillin is high
B. Mycelial mass increases
C. pH increase
D. Both (a) and (b)

17. Inoculum preparation for the fermentation medium for penicillin takes place on

A. wheat seeds
B. barley seeds
C. rice seeds
D. all of these

18. Antibiotics are typically produced in fed-batch reactors because

A. antibiotic yields are generally higher when cells enter the stationary phase
B. the precursors are often toxic to the cells
C. antibiotic yields are generally higher when cell growth slows
D. All of the above

19. Which of the following event occurs during the third phase of the growth of P chrysogenum?

A. Concentration of antibiotic increases in the medium
B. Autolysis of the medium starts
C. Slight rise in pH due to liberation of ammonia
D. All of the above

20. Vegetable oil, (corn oil or soybean oil) added in the fermentation medium for penicillin, act as

A. source of nutrients
B. carbon source
C. antifoam agent
D. both (a) and (c)