Which term describes bacteria that grow in the absence of oxygen and are destroyed by oxygen?

Which term describes bacteria that grow in the absence of oxygen and are destroyed by oxygen?

• A. Anaerobes
• B. Facultative Anaerobes
• C. Endospores
• D. Fungi

Answer: (A)

Bacteria are categorized by how they handle oxygen. Those that grow only when oxygen is absent and are harmed or killed by its presence are called anaerobes. This fits the description because the question specifies growth in the absence of oxygen and destruction by oxygen. Oxygen can be toxic to these organisms because they lack the protective enzymes that detoxify reactive oxygen species, so they don’t survive exposure to air. In contrast, organisms that can grow with or without oxygen are facultative anaerobes, so they aren’t destroyed by oxygen. Endospores are a dormant, highly resistant form that helps some bacteria survive harsh conditions, not specifically about how they respond to oxygen. Fungi are a different kingdom altogether and aren’t described by this bacterial oxygen requirement.

Bacteria are categorized by how they handle oxygen. Those that grow only when oxygen is absent and are harmed or killed by its presence are called anaerobes. This fits the description because the question specifies growth in the absence of oxygen and destruction by oxygen. Oxygen can be toxic to these organisms because they lack the protective enzymes that detoxify reactive oxygen species, so they don’t survive exposure to air.

In contrast, organisms that can grow with or without oxygen are facultative anaerobes, so they aren’t destroyed by oxygen. Endospores are a dormant, highly resistant form that helps some bacteria survive harsh conditions, not specifically about how they respond to oxygen. Fungi are a different kingdom altogether and aren’t described by this bacterial oxygen requirement.