Exercise 10

Question 1

Why can you find anaerobes in the oral cavity? Of what medical importance is this finding?

Answer 1

Areas around and underneath the gums are often anaerobic. This provides conditions for decay and for the development of anaerobes which may contribute to periodontal infections.

Question 2

What does a catalase test indicate about an organism?

Answer 2

The test indicates whether the organism possesses the catalase enzyme which can break down H2O2 which forms during aerobic metabolism. It indicates the organism can probably grow in the presence of oxygen.

Question 3

Which cultures grow in an anaerobic environment?

Answer 3

Clostridium, E. coli, and soil sample

Question 4

Which cultures grow in an aerobic environment?

Answer 4

E. coli, sarcina, and soil sample

Question 5

Which cultures grow in aerobic and anerobic environments?

Answer 5

E. coli, soil sample

Question 6

What is the difference between a candle jar and an anaerobe jar in creating anaerobic conditions?

Answer 6

A candle jar creates a CO2 environment which will help microaerophiles to grow while an anaerobe jar creates an anaerobic environment with H2 and CO2 gases.