Question

1. in biochemical terms, explain what causes lactic acid (sometimes called “lactate”) buildup?

Explanation:

Lactic acid buildup occurs due to anaerobic glycolysis. When oxygen is limited (e.g., during intense exercise), pyruvate (from glucose breakdown) is converted to lactate by lactate dehydrogenase instead of entering the mitochondria for aerobic respiration (as in the citric acid cycle). This regenerates NAD+ to keep glycolysis (which produces some ATP) going.

Answer:

Lactic acid buildup is caused by anaerobic glycolysis. When oxygen is scarce, pyruvate is converted to lactate (lactic acid) by lactate dehydrogenase to regenerate NAD+ for continued glycolysis (ATP production without sufficient oxygen for aerobic respiration).