Bio Vocab 6

Respiration

process of exchanging gases between the atmosphere and body cells

Tracheostomy

procedure where a tube is inserted into the trachea to bypass an airway obstruction

Surfactant

substance that reduces surface tension in the alveoli to prevent collapse

Nostrils

external openings of the nose that allow air to enter

Bronchi

two branches from the trachea that carry air into each lung

Respiratory cycle

one inspiration followed by one expiration

Nasal cavity

inside of the nose containing blood vessels that warm, moisten, and filter air

Bronchioles

smaller branches of the bronchi that control airflow within the lungs

Tidal volume

amount of air moved in or out during a normal breath (~500 mL)

Nasal septum

structure that separates the two nostrils

Alveoli

tiny air sacs where gas exchange occurs with the blood

Functional residual capacity

air remaining in lungs after a normal exhale (~2300 mL)

Glottis

space between the vocal cords

Lungs

soft, spongy organs where gas exchange occurs

Residual volume

air that remains in lungs and cannot be exhaled (~1200 mL)

Sinuses

air-filled cavities in the skull lined with mucus membranes

Pleural cavity

space surrounding the lungs that helps reduce friction during breathing

Vital capacity

maximum amount of air exhaled after a deep breath (~4600 mL)

Pharynx

passageway connecting the nasal cavity to the larynx (shared with digestive system)

Lobules

small subdivisions of the lungs

Total lung capacity

total amount of air lungs can hold (VC + RV)

Larynx

voice box made of cartilage that contains vocal cords

Inspiration

process of inhaling air into the lungs

Respiratory center

part of the brain that controls breathing rate

Epiglottis

flap that closes over the trachea during swallowing

Expiration

process of exhaling air from the lungs

Medulla oblongata

brain region that controls involuntary breathing

Vocal cords

elastic tissues that vibrate to produce sound

Central chemoreceptors

receptors in the medulla that monitor CO₂ levels and blood pH

Peripheral chemoreceptors

receptors that monitor oxygen levels in blood (carotid artery & aorta)

Diaphragm

muscle below the lungs that contracts to allow inhalation

Intercostal muscles

muscles between ribs that assist in breathing

Partial pressure

force exerted by a single gas in a mixture

Trachea

windpipe that connects the pharynx to the lungs

Atmospheric pressure

pressure exerted by air (about 760 mmHg at sea level)

Anoxia

absence of oxygen in body tissues

Atelectasis

collapse of part or all of a lung

Asphyxia

condition caused by lack of oxygen leading to suffocation