L7_Bacterial Structure and Function 2

Question 1

Describe the Flagellum of prokaryotes

Answer 1

A stiff corkscrew like structure that is rotated by a molecular motor embedded through the wall and driven by a proton gradient across the membrane.

Question 2

What do the following drugs do to bacteria? Aminoglycosides, Tertracyclines, Macrolides

Answer 2

Aminoglycosides - Attack small subunit, interfere with initiation
Tertracyclines- Attack small subunit, transfer of t-RNA+aa sets to ribosome
Macrolides- Attack rRNA of large subunit

Question 3

What is the rate limiting step in binary fission?

Answer 3

DNA replication

Question 4

What size are bacterial ribosomes?

Answer 4

70S

Question 5

Describe the make up of a spore, name two bacteria that can form them.

Answer 5

Very rugged, dehydrated package containing the bacterial genome with a minimal entourage of macromolecule. The spore can survive all normal cleaning and sets the standard for autoclaving. when nutrients and water returns the spore can unpack back into vegetative cells. Bacillus and Clostridium

Question 6

What are the growth phases bacteria undergo when in a culture vessel of limited size?

Answer 6

Lag, Log, stationary, death

Question 7

What determines a bacterias tolerance to oxygen?

Answer 7

The ability to breakdown and detoxify oxygen radicals using superoxide dimutase, catalase, and cytochrome C.

Question 8

What is a bacteria that encode for both fermentation and respiration pathways? give and example

Answer 8

Facultative anaerobe (E. Coli)

Question 9

What is bacteria that can withstand oxygen radicals but lacks an ETC?

Answer 9

Aerotolerant Anaerobe

Question 10

What is a bacteria that requires ETC as its source of energy? Give an example

Answer 10

Obligate Aerobe (M. Tuberculosis)

Question 11

What is a bacteria that cannot tolerate oxygen? Give and example

Answer 11

Obligate Anaerobe (C. botulinum)