Purpose of Anaerobic Respiration

Anaerobic respiration occurs in oxygen-poor marsh muds.
••• mud flats image by Stacey Lynn Payne from Fotolia.com

The purpose of respiration in general is to turn food into energy that a living biological cell can use. Anaerobic respiration is respiration that uses any molecule besides oxygen to do this. Many bacteria use anaerobic respiration.

Anaerobic vs. Aerobic Respiration

Aerobic respiration--which includes turning molecular oxygen into carbon dioxide--produces much more energy per unit of food than anaerobic respiration. In most parts of the world, living things that use aerobic respiration have a competitive advantage over living things that can't. However, anaerobes still dominate where oxygen levels are very low.

Facultative vs. Obligate Anaerobes

A facultative anaerobe can use aerobic respiration pathways when it has access to oxygen, and anaerobic pathways when it doesn't. An obligate anaerobe can only use anaerobic pathways, and in many cases cannot tolerate the presence of molecular oxygen in their environment at all.

History

All respiration was anaerobic when life on Earth first began. Photosynthesis produced oxygen as a toxic waste product until enough free molecular oxygen accumulated in the early atmosphere. This oxygen killed the vast majority of life at the time, until organisms developed systems to handle oxygen effectively and use it for aerobic respiration.

Related Articles

How Do Bacteria Respire?
Type of Energy Produced by Photosynthesis
Do All Cells Have Mitochondria?
The Advantages of Anaerobic Respiration
How are Respiration & Combustion of Gasoline Similar?
What Happens to Carbon Dioxide During Photosynthesis?
What Are the Five Subdivisions of Kingdoms?
How Do Living Things Use Energy?
What Is the Purpose of Breathing?
Where Does Respiration Occur?
Can Eukaryotes Survive Without Mitochondria?
How Are Photosynthesis & Cellular Respiration Related?
What Type of Organisms Use Cellular Respiration?
What Is the Optimum pH for Human Stomach Enzyme Activity?
How Are Bacteria a Part of Recycling & Biodegrading?
Where Do Bacteria Live?
Respiration in Plants & Animals
Importance of Aerobic Cellular Respiration
What Are Some Common Uses of Yeast?