27 Ventilation and Gas Exchange Review

These flashcards cover key concepts related to ventilation, gas exchange, and the physiological mechanisms involved in breathing and airway regulation.

What are alveoli and why are they important?

Alveoli are the site of gas exchange in the lungs, covered with pulmonary blood vessels and elastic fibers.

What do Type I and Type II cells in the alveoli do?

Type I cells are responsible for gas exchange, while Type II cells secrete surfactant to improve alveolar expansion.

What does Boyle's Law state regarding pressure and volume?

Boyle's Law states that pressure and volume have an inverse relationship; if the volume of a gas decreases, the pressure increases, and vice versa.

What is the process of breathing called?

Breathing or ventilation is the process of moving gases in and out of the lungs following their partial pressure gradients.

What causes air to move into the lungs?

Air moves into the lungs when the air pressure outside (Patm) is higher than the air pressure inside the lungs (Palv).

What role do the diaphragm and intercostals play in breathing?

The diaphragm and intercostals change the volume of the thoracic cavity, affecting the pressure inside the lungs to facilitate inhalation and exhalation.

What can happen during a pneumothorax?

A pneumothorax occurs when atmospheric pressure equalizes with intrapleural pressure, causing the lung to collapse.

What is the role of bronchodilators in airway regulation?

Bronchodilators, such as epinephrine at Beta2 adrenergic receptors, relax smooth muscle, decrease resistance, and increase airflow.

How does histamine affect the airways during an allergic reaction?

Histamine released during allergic reactions can cause bronchoconstriction, making it hard to breathe, by binding to bronchioles.

What is the effect of leukotrienes on the airways?

Leukotrienes are signal molecules that cause bronchoconstriction and inflammation, important in conditions like asthma.