Chapter 22 MCP: Respiratory System Vocabulary

50 vocabulary flashcards covering key terms and definitions from the Chapter 22 MCP respiratory notes.

Upper respiratory tract

Anatomical structures within the head and neck that conduct air and filter it before reaching the lungs.

Lower respiratory tract

Anatomical structures in the thorax that contain the lungs and airways below the larynx.

Dorsum nasi

The bridge of the nose; the dorsal surface of the nose (the nasal bridge).

Philtrum

The vertical groove between the nose and the upper lip.

Pharynx

The throat; a muscular tube that is shared by the respiratory and digestive systems and has three regions (nasopharynx, oropharynx, laryngopharynx).

Nasopharynx

Region of the pharynx posterior to the nasal cavities, superior to the soft palate.

Oropharynx

Region of the pharynx posterior to the oral cavity; passage for air and food.

Thyroid cartilage

The largest cartilage of the larynx; supports the laryngeal structure and protects the glottis.

Arytenoids, corniculate, and cuneiform cartilages

Laryngeal cartilages that help control and position the vocal cords for sound production.

Trachea

The airway from the larynx to the bronchi; reinforced with C-shaped cartilage; conducts air to the lungs.

Bronchi

Main airways that extend from the trachea into the lungs and branch into smaller bronchioles.

Hilum

The site where bronchi, pulmonary vessels, nerves, and lymphatics enter and exit the lung; alveoli do not pass through.

Alveoli

Tiny air sacs where gas exchange occurs; single-layer walls; lined by Type I cells with Type II surfactant-secreting cells; highly vascularized.

Bronchioles

Small airways branching from the smallest bronchi to the alveolar ducts; lack cartilage.

Type I alveolar cell

Squamous epithelial cell forming the thin walls of the alveoli for gas exchange.

Type II alveolar cell

Cuboidal cells that secrete pulmonary surfactant to reduce surface tension.

Alveolar macrophages

Phagocytic cells in alveolar spaces that remove debris and pathogens.

Parietal pleura

A serous membrane that lines the walls of the thoracic cavity.

Visceral pleura

The serous membrane that directly covers the lungs and extends into lung fissures.

Right lung lobes

Three lobes: superior, middle, and inferior.

Left lung lobes

Two lobes: superior and inferior.

Pulmonary ventilation

Breathing; movement of air into and out of the lungs driven by pressure differences between intrapulmonary/intra-alveolar spaces and the atmosphere.

Intrapulmonary pressure

The pressure inside the alveoli.

Intrapleural pressure

The pressure within the pleural cavity between the two pleural membranes.

Inspiration

Inhalation; external intercostal muscles contract, lifting ribs and expanding the thoracic cavity.

Expiration

Exhalation; external intercostal muscles relax and the ribs return to their resting position.

Tidal volume

The amount of air normally entering the lungs during quiet breathing.

Expiratory reserve volume

The extra volume of air exhaled after a normal tidal expiration.

Inspiratory reserve volume

The extra air that can be drawn into the lungs with a forced inspiration.

Residual volume

The amount of air remaining in the lungs after a maximal exhalation.

Functional residual capacity

The volume remaining in the lungs after a normal exhalation (ERV + RV).

Boyle’s law

Gas volume is inversely proportional to pressure (at constant temperature).

Dalton’s law

In a mixture of gases, the total pressure is the sum of the partial pressures of the components.

Henry’s law

Gases dissolve in liquids in proportion to their solubility and the partial pressure gradient.

Fick’s law

The rate of gas diffusion is proportional to surface area, concentration gradient, permeability, and inversely proportional to membrane thickness.

Hemoglobin

A complex protein in red blood cells that binds oxygen (via iron) and assists in CO2 transport.

Bicarbonate ions

Most carbon dioxide is transported in the blood as bicarbonate (HCO3−) after conversion by carbonic anhydrase.

Ventilation-perfusion coupling

Matching of air flow (ventilation) with blood flow (perfusion) in the lungs for efficient gas exchange.

Bohr effect

Hemoglobin’s decreased affinity for oxygen at lower pH (higher CO2).

Carbonic anhydrase

An enzyme in red blood cells that catalyzes the conversion of CO2 and water to bicarbonate and hydrogen ions.

Respiratory rate

The total number of breaths taken per minute.

Dorsal respiratory group

Medullary neurons that help set the basic rhythm of breathing.

Apneustic center

A pons-based center that stimulates a deeper inspiration by activating the DRG.

Medulla oblongata

Brainstem region housing the dorsal and ventral respiratory groups involved in breathing control.

CO2 as primary driver

Rising carbon dioxide levels in the blood stimulate respiration via central chemoreceptors.

Upper respiratory tract

Structures in the nasal cavity, pharynx, and larynx that filter, warm, and conduct air.

Entrance and exit for respiratory system

Main entry/exit routes for air are the nose and mouth.

Oropharynx

Part of the pharynx behind the oral cavity; passage for air and food.

Larynx

Voice box; connects the pharynx to the trachea and houses the vocal cords.

Laryngeal elevation

During swallowing, the larynx elevates to help move food and protect the airway.