Respiratory System – Page 1 Vocabulary

Vocabulary flashcards covering key terms from Page 1 notes on respiratory structure, function, defense, and anatomy.

Respiratory membrane

The thin barrier across which gas exchange occurs between alveoli and pulmonary capillaries; driven by pressure gradients; oxygen diffuses into blood and carbon dioxide diffuses out.

Gas exchange

The diffusion of oxygen into the blood and carbon dioxide out of the blood across the respiratory membrane.

Oxygen diffusion

Movement of oxygen from alveolar air into the blood.

Carbon dioxide diffusion

Movement of carbon dioxide from the blood into the alveolar air to be exhaled.

Thermoregulation

Regulation of body temperature by the respiratory system, including warming/humidifying inhaled air and releasing heat via exhalation.

Nasal passages

Upper airway region where air is warmed, humidified, and filtered; part of the respiratory tract.

Trachea

The windpipe; a main airway that conducts air from the larynx to the bronchi.

Primary bronchus

The main airway that forks from the trachea into each lung.

Secondary bronchus

Branch of the primary bronchus that supplies a lobe of the lung.

Tertiary bronchus

Branch of the secondary bronchus that supplies a bronchopulmonary segment.

Bronchioles

Small airways following the bronchi leading toward the gas exchange regions.

Terminal bronchioles

The last conducting airways before the respiratory zone; lead to respiratory bronchioles.

Respiratory bronchioles

Small airways that contain some alveoli and mark the start of gas exchange.

Alveolar ducts

Ducts that lead to alveolar sacs and end in clusters of alveoli.

Alveolar sacs

Clusters of alveoli at the end of alveolar ducts where gas exchange occurs.

Alveoli

Tiny air sacs where gas exchange occurs between air and blood.

Pleura

A serous membrane surrounding the lungs and lining the thoracic cavity.

Parietal pleura

The portion of the pleura that lines the walls of the thoracic cavity.

Visceral pleura

The portion of the pleura that covers the surface of the lungs.

Mediastinum

The central thoracic cavity region that separates the two lungs and contains the heart and major vessels.

Hilum

The region where primary bronchi, blood vessels, and nerves enter/exit each lung.

Cardiac notch

A heart-shaped indentation on the left lung accommodating the heart.

Larynx

The voice box; part of the upper airway containing vocal cords.

Pulmonary artery

The vessel that carries deoxygenated blood from the heart to the lungs for oxygenation.

Pulmonary vein

The vessel that returns oxygenated blood from the lungs to the heart.

Cilia

Hairlike projections lining the respiratory tract that move mucus and trapped debris out of the airways.

Mucus

A sticky secretion that traps particulate matter in the airways.

Lysozyme

An enzyme in mucus that helps break down bacteria.

Immunoglobulin A (IgA)

An antibody produced in mucosal linings that neutralizes pathogens.

Mast cell

An immune cell that releases inflammatory chemicals to increase blood flow during threats.

Macrophage

A large phagocytic cell that engulfs particulates and pathogens in lung tissue.

Particulate matter

Inhaled particles that can cause disease; filtered by mucus and cilia in the airways.