Aerobic Energy Production and Respiration Quiz

Respiratory Physiology

• The VD/VT ratio increases due to an increase in physiological dead space and a decrease in alveolar ventilation.

Oxygen Levels and Exercise

• Oxygen levels in muscle decrease around 50% of maximal work rate.
• At maximal exercise, arterial PO2 levels decrease, while alveolar PO2 levels remain relatively constant.
• Mean capillary and myoglobin O2 levels decrease at maximal exercise compared to rest.

Gas Exchange and Respiration

• The atmospheric pressure at sea level is 760 mm Hg.
• Oxygen levels (mm Hg) decrease from the atmosphere to the mitochondria due to the gradient of oxygen partial pressure.
• Exercise-induced arterial hypoxemia (EIAH) is a condition where arterial oxygen levels decrease during exercise.
• Respiration is the process of gas exchange between the atmosphere and the body's cells.

Ventilation and Exercise

• Hyperpnea is an increased rate of ventilation, which occurs during exercise.
• Ventilatory drift is a gradual increase in ventilation during prolonged exercise, which helps to maintain arterial CO2 levels.
• The measure of gas exchange efficiency is the VD/VT ratio.
• The primary factor responsible for the initial increase in minute ventilation is the increase in CO2 production.
• Three factors that influence ventilation during exercise are CO2 production, O2 demand, and temperature regulation.
• The function of ventilatory drift is to maintain a stable CO2 level in the blood.

Blood Transport and Oxygen

• The majority of CO2 transport occurs in the blood in the form of bicarbonate ions.
• The oxyhemoglobin dissociation curve represents the binding of oxygen to hemoglobin.
• A left shift in the oxyhemoglobin dissociation curve indicates increased oxygen binding to hemoglobin.
• The a-vO2 difference indicates the amount of oxygen extracted from the blood by the tissues.

Acid-Base Balance

• The source of H+ in the bicarbonate buffering system is the metabolism of CO2 and water.
• Increasing ventilation helps to restore acid-base balance by increasing the exhalation of CO2.

Formulas

• The formula for minute ventilation (VE) is VE = f x VT, where f is the respiratory frequency and VT is the tidal volume.
• The formula for alveolar ventilation (VA) is VA = f x (VT - VD), where VD is the physiological dead space.