BIO 411 Exam 2 Questions with Answers (100% Correct Answers)

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BIO 411 Exam 2 Questions with Answers (100% Correct
Answers)

Obligate aerobes oxygen requirement Answer: Require oxygen

Facultative anaerobes oxygen requirement Answer: Don't require

oxygen

Obligate anaerobes oxygen requirement Answer: Oxygen is toxic to

them

Aerotolerant anaerobes oxygen requirement Answer: Tolerate, but
cannot use oxygen

Microaerophiles oxygen requirement Answer: Require oxygen lower
than air

Examples of obligate aerobes Answer: 1. M. tuberculosis

2. N. asteroides

Examples of facultative anaerobes Answer: 1. Staph. spp.

2. Strep. spp.


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3. E. coli

4. Salmonella

5. Listeria spp.

Examples of obligate anaerobes Answer: 1. Actinomyces

2. Bacteroides

3. Clostridium

4. Fusobacterium

Examples of aerotolerant anaerobes Answer: 1. Strep. mutans

Examples of microaerophiles Answer: 1. Campylobacter spp.

Where do obligate aerobes grow in the tube Answer: Top

Where do facultative anaerobes grow in the tube Answer: Top/spread
out

Where do obligate anaerobes grow in the tube Answer: Bottom

Where do aerotolerant anaerobes grow in the tube Answer: Spread out



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Where do microaerophiles grow in the tube Answer: Middle

Chemically defined media Answer: Exact chemical composition is

known

Complex media Answer: - Has nutrients

- Contains broth, agar, and TSB

Reducing media Answer: - Used to make anaerobic bacteria

- Contains chemicals (sodium thioglycolate)

- Heated to kill off O2

Selective media Answer: - Suppresses unwanted microbes and

encourages wanted microbes

- Contains inhibitors (EMB, mannitol agar, MacConkey agar)

Selective media example (EMB) Answer: EMB dye is toxic for gram
positive bacteria, so it's a selective media for gram negative bacteria

Differential media Answer: Allows growth of several different colonies
on the same plate



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