Growth

Question 1

Bacteria reproduce by…………… , whereas eukaryotic cells reproduce by
……………. .

Answer 1

1. binary fission

2. mitosis

Question 2

The bacterial growth cycle consists of four phases:

Answer 2

the #lag phase, during which
nutrients are incorporated; the #log phase, during which rapid cell division
occurs; the #stationary phase, during which as many cells are dying as are being formed; and the #death phase, during which most of the cells are dying because
nutrients have been exhausted.

Question 3

Some bacteria can grow in the presence of oxygen ,………………. and………………..
but others die in the presence of oxygen……………… .

Answer 3

1. Aerobes and facultative

2. anaerobes

Question 4

The use of oxygen by

bacteria generates toxic products such as…………….. and…………………….. .

Answer 4

Superoxide and hydrogen peroxide

Question 5

Aerobes and facultatives have enzymes, such as…………………. and
………………… , that detoxify these products, but anaerobes do not and are killed in the
presence of oxygen.

Answer 5

Superoxide dismutase and catalase

Question 6

Fermentation of sugars, such as glucose, results in

the production of………… and………………. or…………….. .

Answer 6

ATP and Pyruvic acid and Lactic acid

Question 7

Pyrovi acid and Lactic acid lower the

pH, and this can be detected by the change in color of indicator dyes.

Answer 7

True

Question 8

depicts a bacterial growth curve divided into phases a, b, c, and d. In
which one of the phases are antibiotics such as penicillin most likely to kill
bacteria?

Answer 8

Phase b

Question 9

Some bacteria are obligate anaerobes. Which of the statements best
explains this phenomenon?

Answer 9

They lack superoxide dismutase and catalase