Response：练习题

• a.

  \(Q = \text{end-diastolic volume} - \text{end-systolic volume}\)

• b.

  \(Q = \text{systolic blood pressure} + \text{diastolic blood pressure}\)

• c.

  \(Q = \text{stroke volume} \times \text{heart rate}\)

• d.

  \(Q = \text{ventilation rate} \times \text{tidal volume}\)

• a.

  Both insulin and glucagon concentrations decrease to maintain a state of metabolic rest.

• b.

  Both insulin and glucagon concentrations increase to maximize glucose uptake.

• c.

  Plasma insulin concentration decreases and plasma glucagon concentration increases.

• d.

  Plasma insulin concentration increases and plasma glucagon concentration decreases.

• a.They detect a decrease in blood pH and an increase in \( PCO_{2} \), stimulating the respiratory center to increase ventilation.
• b.They detect a decrease in blood glucose levels, which triggers deeper breaths.
• c.They detect an increase in blood pH, which signals the lungs to slow down breathing.
• d.They detect a decrease in body temperature, causing a rise in tidal volume.

• a.

  It decreases steadily as heart rate increases to prevent overfilling the heart.

• b.

  It increases until it plateaus at approximately 40%–60% of \(VO_{2}max\).

• c.

  It remains constant because only heart rate contributes to increased cardiac output.

• d.

  It increases linearly with exercise intensity until maximal exhaustion is reached.

• a.

  Increased reliance on aerobic glycolysis and oxidative phosphorylation.

• b.

  Depletion of adenosine triphosphate (ATP) and phosphocreatine (PCr) stores.

• c.

  Rapid breakdown of glycogen stores to produce lactate.

• d.

  Increased fatty acid oxidation as the main energy source.

先自己写一遍答案，再对照解题步骤。

先自己写一遍答案，再对照解题步骤。

先自己写一遍答案，再对照解题步骤。