A&P II RESPIRATORY SYSTEM

What are the major functions of the respiratory system?

To supply the body with O2 for cellular respiration and dispose of CO2, a waste product of cellular respiration.

What are the four processes involved in respiration?

Pulmonary ventilation, external respiration, transport of O2 and CO2 in blood, and internal respiration.

What is pulmonary ventilation?

The movement of air into and out of the lungs.

What is external respiration?

The exchange of O2 and CO2 between the lungs and blood.

What is internal respiration?

The exchange of O2 and CO2 between systemic blood vessels and tissues.

What are the two phases of pulmonary ventilation?

Inspiration (inhalation) and expiration (exhalation).

What is atmospheric pressure at sea level?

760 mm Hg, equal to 1 atmosphere.

What does negative respiratory pressure indicate?

Pressure that is lower than atmospheric pressure (Patm).

What happens to intrapulmonary pressure during inspiration?

Intrapulmonary pressure decreases as lung volume increases.

What is transpulmonary pressure?

The difference between intrapulmonary pressure (Ppul) and intrapleural pressure (Pip).

What condition is caused by a pneumothorax?

Collapse of the lungs due to disruption of negative pressure in the pleural cavity.

What is Boyle's Law regarding gas?

Pressure (P) varies inversely with volume (V).

How does quiet expiration occur?

It is a passive process; inspiratory muscles relax, thoracic cavity volume decreases, and lungs recoil.

What influences resistance in airway passages during breathing?

Friction is the major nonelastic source of resistance to gas flow.

What is surfactant?

A detergent-like lipid and protein complex that helps reduce surface tension of alveolar fluid.

What is tidal volume (TV)?

The amount of air moved into and out of the lung with each breath, averaging about 500 mL.

What is the formula for calculating respiratory capacities?

Respiratory capacities are combinations of two or more respiratory volumes.

What does forced vital capacity (FVC) measure?

The amount of gas forcibly expelled after taking a deep breath.

How does the composition of alveolar gas differ from atmospheric air?

Alveoli contain more CO2 and water vapor due to gas exchanges and humidification.

What is Dalton's law of partial pressures?

The total pressure exerted by a mixture of gases equals the sum of the pressures exerted by each gas.

How is oxygen transported in the blood?

1.5% is dissolved in plasma and 98.5% is bound to hemoglobin (Hb) in red blood cells.

What is the oxygen-hemoglobin dissociation curve?

A graph plotting percent of Hb saturation against PO2 concentrations.

How does pH affect hemoglobin's affinity for oxygen?

Decreased pH (acidosis) weakens the Hb-O2 bond, promoting O2 unloading.

What is hypoxia?

Inadequate O2 delivery to tissues.

What is carbon monoxide poisoning?

When carbon monoxide binds to hemoglobin, preventing oxygen from binding.

How does the body acclimatize to high altitude?

Increased erythropoietin production to raise red blood cell count for improved oxygen transport.

What are the symptoms of acute mountain sickness?

Headaches, shortness of breath, nausea, and dizziness.

What does internal respiration involve?

Capillary gas exchange in body tissues, with reversed partial pressures compared to external respiration.

How does ventilation-perfusion coupling function?

It matches alveolar ventilation with pulmonary perfusion for efficient gas exchange.

What is the effect of increasing CO2 on ventilation?

High CO2 levels lead to bronchiole dilation to eliminate CO2 more rapidly.

What are anatomical and alveolar dead space?

Anatomical dead space consists of air that does not contribute to gas exchange; alveolar dead space involves nonfunctional alveoli.

What is forced expiratory volume in 1 second (FEV1)?

The amount of gas expelled in the first second of a forced vital capacity measurement.

What happens to blood pH with slow, shallow breathing?

CO2 levels increase, causing a drop in pH.

What is the primary role of the respiratory system in acid-base balance?

Breathing adjusts blood pH by altering CO2 levels.

What condition does hyperventilation lead to?

Decreased blood CO2 levels (hypocapnia) and potential dizziness or fainting.

What is the most soluble gas in water compared to O2?

CO2 is 20 times more soluble in water than O2.