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. Muscles are getting rid of carbon dioxide by the Krebs cycle.
B. Muscles are building up lactate from anaerobic respiration.
C. Electron transport chains in the mitochondria are producing too much ATP.
D. Glycolysis is producing too much pyruvate from the high glucose levels in the body.
B. Muscles are building up lactate from anaerobic respiration.
Explanation:
During excessive physical activities such as sprinting, muscles carry out anaerobic respiration to compensate the need of ATP for their continuous contraction. It is done since oxygen availability can not meet the increased demand of ATP during excess physical activities. Anaerobic respiration in muscles converts pyruvate into lactate which in turn causes burning sensation in muscles. Hence, her symptoms are due to increased oxygen demand and buildup of lactate in muscles.
