Cardiopulmonary Anatomy and Physiology Flashcards

Which of the following best describes the primary function of the alveoli?

Answer: Gas exchange between air and blood

Alveoli are the primary sites of gas exchange where oxygen diffuses into the blood and carbon dioxide diffuses out.

The normal partial pressure of oxygen (PaO2) in arterial blood at sea level is approximately:

Answer: 80–100 mmHg

Normal PaO2 ranges from 80 to 100 mmHg in a healthy adult breathing room air at sea level.

Which muscle is the primary muscle of inspiration?

Answer: Diaphragm

The diaphragm contracts and flattens during inspiration, generating the pressure gradient that draws air into the lungs.

What is the Bohr effect?

Answer: Increased CO2 shifts the oxyhemoglobin curve right

The Bohr effect describes how elevated CO2 (and decreased pH) reduces hemoglobin's affinity for oxygen, shifting the oxyhemoglobin dissociation curve to the right.

Which lung zone, according to the West zones model, has the greatest blood flow?

Answer: Zone 3 (base)

Zone 3 (base) has the greatest blood flow because both arterial and venous pressures exceed alveolar pressure, keeping pulmonary capillaries continuously open.

Normal cardiac output at rest is approximately:

Answer: 5–6 L/min

Resting cardiac output is typically 5–6 L/min, calculated as heart rate multiplied by stroke volume.