Question

29.
Explain the major pathways of anaerobic respiration starting from Pyruvic acid​

Answer 1

Answer:

Under anaerobic conditions, the absence of oxygen, pyruvic acid can be routed by the organism into one of three pathways: lactic acid fermentation, alcohol fermentation, or cellular (anaerobic) respiration. ... Humans ferment lactic acid in muscles where oxygen becomes depleted, resulting in localized anaerobic conditions.

Answer 2

In the presence of oxygen most organisms will go through cellular respiration to produce ATP, but some organisms have developed a way to create ATP without oxygen. This process is called fermentation.

Fermentation is much less efficient (aka it creates much less ATP than aerobic cellular respiration), it is only done in anaerobic conditions (when there is no air.)

There are many different types of fermentation: one that occurs in your body is lactic acid fermentation. It starts with same raw materials as aerobic cellular respiration minus the oxygen. Glucose still goes through glycolysis which creates the pyruvic acid and net 2 ATP, but in order to regenerate more NAD the pyruvic acid is then broken down into lactic acid.