Question

Sometimes higher plants and animal to perform anaerobic respiration respiration give scientific reason

Answer 1

Hey :) I am not sure about what the exact answer might be, but here are some value points which can help:

-abscence of favourable conditions
-organisms switch to anaerobic respiration in presence of unfavourable conditions
-in humans, during rigorous physical activity, the muscle cells respire anaerobically to produce lactic acid which causes muscle cramps. At that time, oxygen reaching the cells is not sufficient, so this process takes place.

Hope these help.

Answer 2

Sometimes to produce some extra energy animal’s or plant’s body burn glucose in the absence of oxygen. There is inadequate supply of oxygen to the cells and this is called anaerobic respiration.  

Explanation:

Animal’s body during workout or strenuous work require more energy than normal so in order to fulfill the energy requirement the muscles work in absence or lack of oxygen. This produces lactic acid which causes pain in muscles. Similar reaction occurs in plants but instead of lactic acid plants produces ethanol. Too much of ethanol or lactic acid is harmful for the cells.