Definition to lactic acid and carbon dioxide?

Lactic acid is an organic acid produced during anaerobic respiration, particularly in muscle cells when oxygen is scarce, leading to the breakdown of glucose for energy. Carbon dioxide is a colorless, odorless gas produced as a byproduct of respiration and combustion, formed when carbon-containing compounds are oxidized. Both substances play crucial roles in metabolic processes, with lactic acid contributing to muscle fatigue and carbon dioxide being expelled from the body through exhalation.