Question

Consider obligate anaerobes, facultative anaerobes, and aerotolerant anaerobes. In what way are they all similar? In what way are they all different?

Answer 1

Obligate anaerobes, facultative anaerobes and aerotolerant anaerobes are similar because all of them can breakdown food into energy without using oxygen. In other words, all of them can perform anaerobic respiration.

However, they are different in their response to the presence of oxygen . Obligate anaerobes die in the presence of oxygen, aerotolerant anaerobes can tolerate oxygen but caanot use to to perform aerobic respiration, and facultative anaerobes can use oxygen if present and it can perform aerobic respiration as well.

We can summarise the answer as:

For the three anaerobes,

Similarity:	All of them can survive without oxygen.
Difference:	Obligate anaerobes cannot tolerate oxygen and dies in its presence. Aerotolerant anaerobes can tolerate oxygen, but cannot use it. Facultative anaerobes can tolerate oxygen and use it for performing aerobic respiration.