16. An open system in which the growth rate is maintained by the removal and addition of media at such a rate as to maintain a constant cell density is called a

A. manostat
B. chemostat
C. turbidostat
D. culturostat

17. Washout in steady-state fermentation occurs when

A. dilution rate is less than the maximum specific growth rate
B. dilution rate is higher than the maximum specific growth rate
C. cell concentration reaches the maximum
D. specific growth rate is maximum

18. Fermentor should be filled with medium up to

A. 65-70%
B. 70-75%
C. 75-80%
D. 80-85%

19. Bacterial growth curve is obtained by plotting

A. number of cells versus time
B. number fo spores versus time
C. log of number of cells versus time
D. log of number of cells survived versus time

20. When intracellular enzymes of whole cells are to be used in a bio-conversion process, it is often necessary to____________the cells.

A. permeabilize
B. lyophilize
C. heat-kill
D. denature