Facultative anaerobes

Definition

Facultative anaerobes are organisms that can survive with or without oxygen. They can metabolize energy aerobically when oxygen is present and switch to anaerobic respiration or fermentation when it is absent.

5 Must Know Facts For Your Next Test

1. Facultative anaerobes are adaptable to both aerobic and anaerobic environments.
2. They play a significant role in the decomposition process by breaking down organic matter in varying oxygen levels.
3. In fungi, facultative anaerobes contribute to their survival and growth in diverse habitats.
4. These organisms possess enzymes such as catalase and superoxide dismutase to detoxify oxygen byproducts.
5. Some pathogenic fungi exhibit facultative anaerobic behavior, aiding their ability to infect hosts with fluctuating oxygen levels.

Review Questions

• What metabolic flexibility do facultative anaerobes possess?
• How do facultative anaerobes benefit fungi in different environments?
• Name two enzymes that help facultative anaerobes detoxify oxygen byproducts.

Related terms

Obligate Aerobes: Organisms that require oxygen for survival and cannot grow without it.

Obligate Anaerobes: Organisms that are poisoned by oxygen and must live in environments devoid of it.

Fermentation: A metabolic process where an organism converts carbohydrates into alcohol or acids without the use of oxygen.