What is true about anaerobes?

Anaerobes are organisms that do not utilize oxygen in their metabolic processes. This characteristic is fundamental to their physiology; they either grow in environments completely devoid of oxygen or rely on fermentation or anaerobic respiration to generate energy. This means that instead of using oxygen as the terminal electron acceptor in cellular respiration, anaerobes utilize other molecules, such as nitrate, sulfate, or even organic molecules, depending on the type of anaerobe and the specific metabolic pathways they possess.

Some anaerobes may be sensitive to oxygen, which can be toxic to them, while others can detoxify oxygen to some extent, but they do not depend on it for survival. Therefore, while some anaerobes can coexist in oxygen-rich environments (as in the case of facultative anaerobes), the defining trait is their inability to use oxygen for metabolism.