Question

question 3 of 10
a soccer player has been sprinting up and down the field. she is breathing very hard and has a burning sensation in her muscles. which of the following is the most likely cause of her symptoms?
a. electron transport chains in the mitochondria are producing too much atp.
b. muscles are getting rid of carbon dioxide by the krebs cycle.
c. glycolysis is producing too much pyruvate from the high glucose levels in the body.
d. muscles are building up lactate from anaerobic respiration.

Explanation:

When a soccer player sprints hard, oxygen demand exceeds supply. Muscles switch to anaerobic respiration. Glycolysis converts glucose to pyruvate. Without enough oxygen, pyruvate is converted to lactate. Lactate buildup causes the burning sensation. Electron transport chains (A) produce ATP aerobically. The Krebs cycle (B) is part of aerobic respiration for CO₂ release. Glycolysis (C) doesn't directly cause the symptom; it's lactate from anaerobic glycolysis (D) that does.

Answer:

D. Muscles are building up lactate from anaerobic respiration.