Microbes in the Environment

Question 1

Name the microbe that is known for surviving in extreme conditions

Answer 1

Extremophiles

Question 2

Which microbes are known to survive at very high temperatures?

Answer 2

Archea

Question 3

Are there any microbes that survive above 95 degrees?

Answer 3

No

Question 4

Is it prokaryotes or eukaryotes that can survive above 65 degrees?

Answer 4

Prokaryotes

Question 5

At which temperature do most pathogens thrive?

Answer 5

37 degrees/body temperature

Question 6

Define obligate aerobes

Answer 6

Require oxygen to survive

Question 7

Define obligate anaerobes

Answer 7

Are harmed by oxygen

Question 8

Define facultative anaerobes

Answer 8

Use oxygen when it is available, but can ferment if not

Question 9

Define microaerophilic

Answer 9

Require oxygen, but only at low levels

Question 10

Define aerotolerant

Answer 10

Are not affected by the presence of oxygen, they do not require it to grow but also will not be affected if it is present

Question 11

Why is oxygen toxic to some microbes?

Answer 11

Due to the production of superoxide free radicals

Question 12

Can anything neutralise superoxide free radicals?

Answer 12

A chemically unstable organism that grows in atmospheric oxygen produces superoxide dismutase, which neutralise superoxide free radicals

Question 13

What factors can affect microbial growth?

Answer 13

Temperature (high/low)
pH (high/low)
Water availability (low)

Question 14

How can we control microbes?

Answer 14

By changing the:
Temperature (boiling/ freezing)
pH (by adding acid)
Water availability (drying/ salting)
Chemical content (by adding cidal or static agents)