Respiratory Physiology Quiz

Carbon Dioxide Transport

• Approximately 90% of carbon dioxide in the blood is transported as bicarbonate ions (HCO3-)

Tidal Volume

• The normal tidal volume (TV) for an average adult at rest is approximately 500 mL.

Inspiratory Reserve Volume

• Inspiratory reserve volume (IRV) measures the amount of air that can be forcibly inhaled beyond normal breathing.

Chemoreceptors and Respiration

• Central chemoreceptors in the medulla oblongata monitor changes in cerebrospinal fluid (CSF) pH, primarily due to CO2 levels.
• Peripheral chemoreceptors located in the carotid and aortic bodies detect changes in blood oxygen (O2) levels and pH.

Vital Capacity

• Vital capacity (VC) represents the maximum amount of air that can be exhaled after a maximal inhalation. It is the sum of tidal volume, inspiratory reserve volume, and expiratory reserve volume.

Diaphragm Function

• The primary function of the diaphragm during breathing is to contract for inhalation, pushing air into the lungs.

External Respiration

• Oxygen (O2) moves from the alveoli (tiny air sacs in the lungs) to the pulmonary capillaries (blood vessels) due to a higher partial pressure of O2 in the alveoli.

Oxygen Transport

• Approximately 98.5% of oxygen in the blood is carried bound to hemoglobin within red blood cells.

Internal Respiration

• Oxygen (O2) moves from the systemic capillaries (blood vessels that supply tissues) into the interstitial fluid and then into cells due to a higher partial pressure of O2 in the capillaries.

Carbon Dioxide Exchange

• Carbon dioxide (CO2) diffuses from the tissues into the blood, and then from the blood into the alveoli due to a higher partial pressure of CO2 in the blood.

Inhalation Muscles

• The diaphragm is the primary muscle responsible for inhalation.
• Accessory muscles, such as the external intercostal muscles, assist in forceful inhalation.

Exhalation Mechanics

• Relaxation of the diaphragm and the external intercostal muscles allows the chest cavity to recoil.
• This increase in pressure in the lungs causes air to be expelled.

Tachypnea

• Tachypnea refers to rapid breathing.

Pulmonary Ventilation

• Pulmonary ventilation involves the movement of air into and out of the lungs.
• This process is driven by pressure gradients created by changes in lung volume.

External Intercostal Muscles

• External intercostal muscles assist in inhalation by pulling the ribs upward and outward.
• This action increases the volume of the thoracic cavity.

Gas Exchange Stage

• Gas exchange occurs primarily during the alveolar stage of respiration, specifically within the alveoli.

Internal Intercostal Muscles

• Internal intercostal muscles assist in forceful expiration by pulling the ribs downwards and inwards.
• This decreases the thoracic cavity volume.

Lung Volume Change

• During inhalation, the lung volume increases as the diaphragm flattens and the rib cage expands.
• These actions create negative pressure in the lungs that draws air in.

Test your knowledge on key concepts of respiratory physiology, including gas exchange, tidal volumes, and the role of chemoreceptors. This quiz covers essential topics related to how our body manages oxygen and carbon dioxide during breathing processes.