Anatomy of the Respiratory System

Study Notes

Nose and Nasal Cavity

Functions include partitioning the nasal cavity, increasing surface area and turbulence, and humidifying/warming air before reaching the pharynx.
Composed of bone, hyaline cartilage, and dense irregular connective tissue.
Structure includes one pair of lateral cartilages and two pairs of alar cartilages.
Nasal cavity is an internal, oblong-shaped space extending from the choanae, divided by the nasal septum.

Pharynx

Functions primarily in transferring air.
Divided into three regions: nasopharynx, oropharynx, and laryngopharynx (superior to inferior order).

Larynx

Contains paired cartilages: arytenoids, corniculate, cuneiform; and unpaired cartilages: thyroid, cricoid, epiglottis.
True vocal cords produce sound located in the larynx.
Glottis is the opening between true vocal cords; vestibular folds represent false vocal cords that protect true vocal cords.
Vocal folds (true vocal cords) are responsible for sound production when air passes through them, creating vibrations.

Trachea

Known as the windpipe, functions to conduct air.
Structured with multiple C-shaped cartilage supports for rigidity.
Posterior region abuts the esophagus, lacking cartilage.
The carina marks the bifurcation of the trachea into left and right primary bronchi.

Bronchial Tree and Lungs

Primary bronchi decrease in size, branching into secondary and tertiary bronchi, then into smaller bronchioles.
Bronchioles are less than 1 mm in diameter, leading to terminal and respiratory bronchioles.
Conduct air and allow for bronchoconstriction and bronchodilation through smooth muscle in walls.
Respiratory bronchioles mark the beginning of the respiratory zone where gas exchange occurs with alveolar ducts and alveoli.

Respiratory Membrane

Composed of capillary endothelium, simple squamous epithelium, shared basement membrane (type I pneumocytes), and surfactant layer (type II pneumocytes).
Facilitates gas exchange in the lungs.

Pleural Membranes and Cavity

Pleura is a serous membrane covering lung surfaces and the thoracic wall, formed by simple squamous epithelium.
Visceral pleura lines the lungs, parietal pleura lines thoracic walls and diaphragm.
Pleural cavity, situated between visceral and parietal layers, contains serous fluid that acts as a lubricant.

Pressure Gradients in Pulmonary Ventilation

Outward pull of the chest and inward pull of the lungs create a "suction" effect that keeps lungs inflated.
Intrapleural pressure is lower than intrapulmonary pressure, maintaining lung expansion; equal pressure results in lung deflation.

Description

Explore the intricate structures and functions of the nose, nasal cavity, pharynx, and larynx. This quiz covers the anatomy and physiological roles of these vital components in the respiratory system. Test your knowledge on cartilages, air processing, and sound production.