Question

why some living organisms have to perform anaerobic respiration​

Answer 1

Anaerobic respiration is a type of respiration that occurs in the absence of oxygen, i.e. glucose molecule is broken down without use of oxygen.

Most of the Eukaryota produce energy currency using aerobic respiration, while some of the Prokaryotic organisms like bacteria and archaea produce energy by anaerobic respiration. They prefer anaerobic mode of respiration because of the habitat in which they live where there is no or less oxygen concentration, i.e. not enough to carry out aerobic respiration. Anaerobic respiration is fast as compared to aerobic respiration and is quick source of energy for organisms.

For example:

• Bacteria living inside the gut of humans could not get enough oxygen because of which it respires anaerobically.
• Some bacteria species that live deep inside the soil or water also respire anaerobically

Answer 2

There exists some prokaryotic organisms that survive exclusively through anaerobic respiration pathways.These organisms do not utilize oxygen to produce Adenosine Triphosphate(ATP).

E.g

Human muscles produce lactic acid during physical activity. Strenous and rapid physical acitivity tax the body heavily resulting in the temporary depletion of oxygen.