Respiratory System Vocabulary

Vocabulary flashcards defining the structures and components of the human respiratory system based on the provided textbook lecture notes.

Cilia

Microscopic structures in the respiratory system that beat toward the back of the throat (up from the lungs and down from the nose) up to $1,000$ times a minute to sweep trapped particles and mucus toward the pharynx.

Nasal cavity

An anatomical structure that warms, moistens, and filters entering air using lining hairs and mucus to keep lung tissue clean and healthy for gas exchange.

Mucus

A thin layer in the nasal cavity that moistens incoming air and traps particles of dust or smoke.

Pharynx

A channel at the back of the mouth containing several openings that channelizes air drawn from the nasal passages into the larynx.

Larynx

A cartilaginous structure, also known as the voice box, that surrounds the upper end of the trachea.

Glottis

The cavity of the larynx.

Epiglottis

A cartilaginous structure associated with the respiratory passage near the larynx.

Trachea

A tube running from the pharynx to the lungs that is held permanently open by C-shaped rings of cartilage in its walls, even during low internal air pressure.

Bronchi

The two tubes (singular: bronchus) formed by the division of the trachea leading into each lung, kept permanently open by irregularly shaped plates of cartilage.

Bronchioles

A mass of very fine branches inside the lungs created by the repeated division of each bronchus.

Alveolar ducts

Many short tubes of equal diameter that branch from the bronchioles and end in air sacs.

Air sacs

Tiny hollow bags located at the end of alveolar ducts that contain bubble-like pockets in their walls.

Alveoli

Bubble-like pockets located in the walls of the air sacs that serve as the respiratory surface of a mammal.