Which type of respiration does not require oxygen?

Anaerobic respiration is the type of respiration that does not require oxygen. This process allows organisms to generate energy in environments where oxygen is scarce or absent. It occurs in some bacteria, yeast, and muscle cells, where glucose is broken down to release energy without utilizing oxygen. The byproducts of this process can include lactic acid in muscles or ethanol and carbon dioxide in yeast, depending on the organism and the type of anaerobic respiration occurring.

Other options involve processes that are connected with the use of oxygen. For instance, aerobic respiration requires oxygen to efficiently produce energy from glucose and typically occurs in most multicellular organisms. Cellular respiration generally encompasses both aerobic and anaerobic processes, but it is commonly associated with aerobic respiration, particularly in higher organisms. Lastly, photosynthesis is not a form of respiration at all; it is the process by which plants convert sunlight into chemical energy, using carbon dioxide and water, and releasing oxygen in the process.