16. Important example(s) of enriched medium/media is/ are

A. Loeffler’s serum slope
B. Bordet-gengou medium
C. Blood agar
D. All of these

17. Cell counting can be carried out by

A. direct microscopic count using petroffhansser counting chamber
B. plate counting
C. membrane filter count
D. all of the above

18. Which of the following techniques may be performed quantitatively to determine the number of bacteria of a particular type?

A. Pour plate
B. Spread plate
C. Both (a) and (b)
D. Streak plate technique

19. Intestinal bacteria can grow in the presence of __________ whereas nonintestinal bacteria are usually inhibited.

A. bile salts
B. low concentration of various dyes
C. sugars
D. low levels of nitrogen

20. Which of the following problem makes it impossible to satisfy all of Koch’s postulates?

A. Microorganism causes serious symptoms in humans
B. Microorganism cannot be isolated in pure culture
C. Species of microorganism is in question
D. Genes from the microorganism cannot be amplified by PCR