Respiratory System Vocab

adenoids

lymphatic tissue in the nasopharynx; pharyngeal tonsils

alveolus (plural: alveoli)

air sac in the lung

apex of the lung

tip or uppermost portion of the lung

base of the lung

the lower portion of the lung

bronchioles

the smallest branches of the bronchi

bronchus (plural: bronchi)

the branch of the trachea (windpipe) that is a passageway into the lung; bronchial tube

carbon dioxide (CO₂)

gas produced by body cells when oxygen and carbon atoms from food combine; exhaled through the lungs

cilia

thin hairs attached to mucous membrane epithelium lining the respiratory tract

diaphragm

muscle separating the chest and abdomen; contracts to pull air into lungs; relaxes to push air out

epiglottis

lid-like piece of cartilage that covers the larynx; keeps food from entering the larynx and trachea during swallowing

expiration

breathing out (exhalation)

glottis

slit-like opening to the larynx

hilum (of lung)

midline region where the bronchi, blood vessels, and nerves enter and exit the lungs

inspiration

breathing in (inhalation)

larynx

voice box; contains the vocal cords

lobe

division of a lung

mediastinum

the region between lungs in the chest cavity; contains the trachea, heart, lymph nodes, aorta, esophagus, and bronchial tubes

nares

opening through the nose carrying air into the nasal cavities

oxygen (O₂)

gas that makes up 21% of air; passes into the bloodstream at the lungs and travels to all body cells

palatine tonsil

one of a pair of almond-shaped masses of lymphatic tissue in the oropharynx

paranasal sinus

one of the air cavities in the bones near the nose

parietal pleura

outer fold of pleura lying closer to the ribs and chest wall

pharynx

the throat; including the nasopharynx, oropharynx, and laryngopharynx

pleura

double-folded membrane surrounding each lung

pleural cavity

space between the folds of the pleura

pulmonary parenchyma

essential parts of the lung, responsible for respiration; bronchioles and alveoli

respiration

the process of moving air into and out of the lungs; breathing

trachea

windpipe

visceral pleura

inner fold of pleura lying closer to the lung tissue