chapter: microbial nutrition and growth

1) In microbiology, the term growth usually refers to an increase in

• A) a microbe's size.

• B) the number of microbial cells.

• C) the amount of ATP produced.

• D) the number and size of microbial cells.

• E) the number and size of microbial cells and the amount of ATP produced.

Answer explanation

Bloom's Rank: Comprehension

Section: Growth Requirements

2) A cell that uses an organic carbon source and obtains energy from light would be called a

• A) photoheterotroph.

• B) lithoautotroph.

• C) photoautotroph.

• D) chemoheterotroph.

• E) chemoautotroph.

Answer explanation

Bloom's Rank: Comprehension

Section: Growth Requirements

3) A(n) __________ organism is one that requires oxygen for growth.

• A) anaerobic

• B) facultative anaerobic

• C) aerotolerant

• D) obligate aerobic

• E) both aerotolerant and anaerobic

Answer explanation

Bloom's Rank: Knowledge

Section: Growth Requirements

4) An aquatic microbe that can grow only at the surface of the water is probably which of the

following?

• A) a phototroph

• B) a heterotroph

• C) a chemotroph

• D) a lithotroph

• E) an anaerobe

Answer explanation

Bloom's Rank: Application

Section: Growth Requirements

5) Which of the following forms of oxygen is detoxified by the enzyme catalase?

• A) singlet oxygen

• B) hydroxyl radical

• C) peroxide anion

• D) superoxide radical

• E) molecular oxygen

Answer explanation

Bloom's Rank: Comprehension

Section: Growth Requirements

6) All of the following are used to protect organisms from the toxic by-products of oxygen

EXCEPT

• A) carotenoids.

• B) superoxide dismutase.

• C) peroxidase.

• D) protease.

• E) catalase.

Answer explanation

Bloom's Rank: Comprehension

Section: Growth Requirements

7) A microbe that grows only at the bottom of a tube of thioglycollate medium is probably a(n)

• A) obligate aerobe.

• B) facultative anaerobe.

• C) aerotolerant anaerobe.

• D) microaerophile.

• E) obligate anaerobe.

Answer explanation

Bloom's Rank: Application

Section: Growth Requirements

8) Nitrogen is a growth limiting nutrient for many organisms because

• A) it is necessary for the biosynthesis of amino acids.

• B) it is required for synthesis of nucleotides.

• C) it is required for lipid synthesis.

• D) only a small number of bacteria are able to extract it from the atmosphere.

• E) only a few microbes can extract it from the atmosphere, but all organisms require it for amino

  acid and nucleotide synthesis.

13) Which of the following organisms would be most likely to contaminate a jar of pickles?

• A) a neutrophile

• B) a thermophile

• C) an acidophile

• D) an obligate anaerobe

• E) a mesophile

Answer explanation

Bloom's Rank: Comprehension

Section: Growth Requirements

14) Organisms that can grow with or without oxygen present are

• A) obligate aerobes.

• B) facultative anaerobes.

• C) aerotolerant anaerobes.

• D) obligate anaerobes.

• E) either facultative anaerobes or aerotolerant anaerobes.

Answer explanation

Bloom's Rank: Comprehension

Section: Growth Requirements