Chapter 6

A microorganism grows in the lab on medium containing mineral salts but no organic compounds. The organism is likely to be a(n):
a) heterotroph
b) chemoheterotroph
c) chemotroph
d) autotroph
e) the answer cannot be determined from the information provided

The ________ method provides an estimate of the CFUs (colony-forming units) in a sample.
a) turbidity
b) direct microscopic count
c) viable plate-count
d) streak plate
e) Coulter counter

An axenic culture is one which:
a) is obtained from a clinical sample.
b) contains only pathogens
c) is grown as a broth culture
d) contains mixed microbiota
e) contains only a pure culture

Rates of cell production and cell death are approximately equal during the ________ phase of growth.
a) death
b) lag
c) intermediate
d) log
e) stationary

Serial dilution can be used in combination with pour plates as a method for isolating pure cultures.
(TRUE/FLASE)

Agar is a useful compound in the microbiology lab because it is an excellent nutrient for bacteria.
(TRUE/FALSE)

A pure culture is composed of cells that arise from a single (CFU/inoculum/sample).

A growth curve plots the (concentration/number/percentage) of viable organisms in a growing population over time.

A clinical sample labeled as "sputum" was collected from:
a) a piece of tissue
b) the lungs
c) the skin
d) the central nervous system
e) the blood

A(n) ________ is a complex community of various types of microbes that adhere to surfaces.
a) inoculum
b) colony
c) aggregate
d) CFU
e) biofilm