41. Postgate assay technique is useful in determining if a cell is viable even though it is

A. incapable of cell division
B. too small to see
C. an obligate aerobe
D. a thermophile

42. What are the extrinsic factors for microbial growth?

A. humidity
B. storage temperature
C. composition of the gas phase
D. all of these

43. Quantitative measurement of bacterial growth can be carried out by measuring

A. cell count
B. cell mass
C. cell activity
D. all of these

44. Organisms such as lactobacilli that have elaborate requirements for specific nutrients i.e. vitamins and other growth-promoting substances are generally called as

A. fastidious heterotrophs
B. chemo-lithotrophs
C. chemotrophs
D. photo-organotrophs

45. The combination of low levels of NaCl, NaNO₃ (sodium nitrate), and slightly acid pH can prevent multiplication and toxin formation of

A. Salmonella
B. S. aureus
C. C. botulinum
D. all of these