You are the manager of a culture collection of

36.
You are the manager of a culture collection of bacteria that have been isolated from diverse environments
around the planet. A bioprospecting company requests an organism from which to isolate a lactase enzyme
that rapidly digests the lactose in milk at fridge temperature (4°C). Which class of organism would you suggest
they study?
A. A thermophile D. A mesophile
B. A psychrophile E. A hyperthermophile
C. A halophile

Test Form: A
37.
Glucose fermentation by some microbes results in the accumulation of acids such as acetate and lactate in the
medium, which are often toxic and dangerous to the cell in high concentrations. The creation of these acid
byproducts is often necessary in order to:
38.
True or False: when DNA polymerase and RNA polymerase collide head‐on, the RNA polymerase is typically
knocked off the DNA molecule while the DNA polymerase hangs on.
39.
The soil bacterium (and opportunistic pathogen) Pseudomonas aeruginosa is capable of generating energy by a
wide variety of processes. Which mode of growth do you think would usually allow Pseudomonas to achieve
the highest possible growth rate?
40.
Carboxysomes and Enterosomes share which feature?
A. A lipid membrane bilayer D. All of the above
B. A shell of protein E. None of the above
C. Contain RuBisCo
41.
Which of the following cellular structures is composed primarily of a phospholipid membrane?

Test Form: A
42.
Say you knew only one thing about an unknown bacterium you are starting to identify. Which of the following
would tell you that it must be Gram‐negative?