Fermentation is a/an ...... process.

Radha was running on a treadmill at a great speed for $15$ minutes continuously. She stopped the treadmill and abruptly came out. For the next few minutes,she was breathing heavily/fast. Answer the following questions.
$(a)$ What happened to her muscles when she did strenuous exercise?
$(b)$ How did her breathing rate change?

Acidic $pH$ of muscles is due to -

In the following flow chart, replace the symbols $a$, $b$, $c$ and $d$ with appropriate terms. Briefly explain the process and give any two applications of it.

In human skeletal muscle,anaerobic respiration leads to the formation of $.....P.....$,and in yeast cells,anaerobic respiration leads to the formation of $.....Q.....$.

What is the fate of pyruvic acid under anaerobic conditions in our body?