4. Bacterial replication is accomplished primarily by
a. mitosis.
b. meiosis.
c. cytokinesis.
d. binary fission.

5. Bacteria that use oxygen, but only at low concentration, are classified as
a. obligate aerobes.
b. microaerophiles.
c. obligate anaerobes.
d. aerotolerant anaerobes.

6. Bacteria that use organic compounds as the source of both carbon and energy are referred to as
a. photoautotrophs.
b. chemoautotrophs.
c. photoheterotrophs.
d. chemoheterotrophs.