When an individual exercises vigorously for more than 15 minutes, the muscle cells are unable to obtain oxygen from the blood quickly enough. As a result, the muscle cells

Question

a
send signals to the brain telling it to shut the muscles down.
b
stop functioning properly, resulting in death.
c
start anaerobic respiration, producing lactic acid buildup.
d
pull oxygen through the skin in order to continue working.

Answer 1

The correct answer is:

c) start anaerobic respiration, producing lactic acid buildup.

During vigorous exercise, when oxygen supply to muscle cells is insufficient, they shift from aerobic respiration (which uses oxygen) to anaerobic respiration, which does not require oxygen. This process leads to the production of lactic acid as a byproduct.