CH 8: The Respiratory System

respiratory system

The organ system responsible for taking in oxygen and expelling carbon dioxide.

nares/nostrils (pl), naris/nostril (sg)

The external openings of the nasal cavity.

nasal septum, septum

The wall of cartilage and bone that divides the nasal cavity into right and left sides.

nasal cavity, nasal, cavity

The hollow space behind the nose that warms, moistens, and filters air.

paranasal sinuses, paranasal, sinus

Air-filled cavities within the bones of the skull that connect to the nasal cavity.

olfactory complex, olfaction, olfactory

The structures involved in the sense of smell.

Eustachian tube

The tube connecting the middle ear to the pharynx; equalizes air pressure.

palate

The roof of the mouth, separating the oral and nasal cavities.

soft palate, hard palate

The muscular rear portion (soft) and the bony front portion (hard) of the roof of the mouth.

pharynx, pharyngeal (adj), pharyngolaryngeal bifurcation

The throat; the passageway where the nasal cavity and oral cavity meet above the splitting point to the larynx and esophagus.

nasopharynx, nasopharyngeal

The upper part of the pharynx, connecting with the nasal cavity above the soft palate.

oropharynx, oropharyngeal (adj)

The middle part of the pharynx behind the mouth, serving as a passage for food and air.

laryngopharynx

The lower part of the pharynx, just above the larynx and esophagus.

larynx, laryngeal (adj)

The voice box; contains the vocal cords and guards the entrance to the trachea.

epiglottis

A leaf-shaped flap of cartilage that covers the larynx during swallowing to prevent food from entering the airway.

glottis

The vocal apparatus of the larynx, consisting of the vocal cords and the opening between them.

thyroid cartilage

The largest cartilage of the larynx; forms the "Adam's apple."

vocal cords

Folds of tissue within the larynx that vibrate to produce sound.

cricoid cartilage

The ring-shaped cartilage forming the lower base of the larynx.

trachea, tracheal (adj)

The windpipe; the main airway extending from the larynx down to the bronchi.

lung

The primary organs of respiration, where gas exchange occurs.

apex

The rounded, superior tip of each lung.

base

The broad, concave inferior surface of each lung resting on the diaphragm.

hilum, hilar

The depression or wedge on the medial surface of a lung where blood vessels and bronchi enter.

lobe, lung, lobar

A major structural division of the lung (three in the right lung, two in the left).

bronchial tree

The branching system of bronchi and bronchioles that conducts air into the lungs.

bronchus (sg), bronchi (pl), bronchial

One of the two primary airway divisions of the trachea leading into the lungs.

bronchioles

The smallest branches of the bronchial tree, leading to the alveoli.

alveoli (pl), alveolus (sg), alveolar

Tiny, microscopic air sacs in the lungs where gas exchange takes place.

pleura (sg), pleurae (pl)

The serous membrane enclosing the lungs and lining the thoracic cavity.

visceral pleura, visceral

The inner layer of pleura attached directly to the surface of the lungs.

parietal pleura, parietal

The outer layer of pleura lining the inner wall of the thoracic cavity.

pleural cavity, pleural space, pleural (adj)

The potential space between the visceral and parietal pleurae.

bifurcate, bifurcation

To divide or fork into two branches.

cilia (pl), cilium (sg)

Hair-like projections on respiratory epithelial cells that sweep mucus and trapped particles away from the lungs.

expectorate

To cough up and spit out mucus or phlegm from the respiratory tract.

foreign body

Any object or substance that has been introduced into the airway from the outside.

membrane

A thin layer of tissue that covers a surface, lines a cavity, or divides a space.

mucus (noun), mucous (adj)

The slimy substance produced by mucous membranes to moisten and protect airways.

mucous membrane

A membrane that lines cavities and tubes that open to the outside of the body.

patent

Open, unobstructed, and affording free passage.

phlegm

Thick mucus secreted by the tissues lining the respiratory passages.

pulmonary

Pertaining to the lungs.

respiratory infection

An infection affecting any part of the body's breathing system.

respiratory tract, tract, upper respiratory tract, lower respiratory tract

The pathway for air; upper includes nose to pharynx; lower includes larynx to alveoli.

SpO2

Oxygen saturation; the percentage of hemoglobin bound to oxygen in the blood.

sputum

Phlegm or mucus expectorated from the respiratory tract mixed with saliva.

viscosity, viscous (adj)

The thickness or resistance to flow of a fluid.

eupnea, eupneic

Normal, unlabored, and quiet breathing.

respiration, respiratory

The process of gas exchange between the atmosphere and cells.

perfusion, pulmonary

The flow of blood through the capillaries of the lungs for gas exchange.

ventilation

The physical movement of air into and out of the lungs (breathing).

external respiration

The exchange of gases between the air in the alveoli and the blood in pulmonary capillaries.

internal respiration

The exchange of gases between the blood in systemic capillaries and tissue cells.

cellular respiration

The metabolic processes within a cell that use oxygen to produce energy (ATP).

respiratory muscles

The muscles that drive ventilation, primarily the diaphragm and intercostals.

diaphragm

The primary muscle of respiration that separates the thoracic and abdominal cavities.

intercostal muscles

Muscles located between the ribs that assist in changing the volume of the chest cavity.

accessory muscles

Muscles of the neck, chest, and abdomen that assist in breathing during heavy exertion or distress.

abdominal muscles

Muscles of the anterior abdominal wall that assist in forced expiration.

airway obstruction, obstruction

A blockage or narrowing of any part of the respiratory tract.

anosmia

The loss of the sense of smell.

aspiration

The accidental drawing of food, liquid, or a foreign object into the airway.

congestion, nasal, sinus or chest/lung

An abnormal accumulation of fluid or mucus in the airway passages or air spaces.

croup

An acute respiratory syndrome in children characterized by a barking cough and stridor.

epiglottitis

Severe, life-threatening inflammation of the epiglottis.

epistaxis

A nosebleed.

influenza

An acute viral infection of the respiratory tract characterized by fever, chills, and muscle aches.

laryngitis

Inflammation of the larynx, causing hoarseness or loss of voice.

pharyngalgia

Pain in the pharynx; a sore throat.

pharyngitis

Inflammation of the pharynx.

rhinorrhea

A runny nose; excessive discharge of mucus from the nasal passages.

rhinitis

Inflammation of the mucous membranes of the nose.

sinusitis

Inflammation of the sinuses.

upper respiratory infection (URI)

An acute infection involving the nasal cavity, pharynx, or larynx (e.g., the common cold).

asthma, asthmatic (adj)

A chronic inflammatory disorder of airways characterized by episodic bronchospasms and wheezing.

atelectasis

The partial or complete collapse of a lung or lobe due to deflated alveoli.

bronchiectasis

Chronic, irreversible dilation and destruction of the bronchi.

bronchiolitis

Inflammation of the bronchioles, common in infants and young children.

bronchitis, chronic bronchitis

Inflammation of the bronchi; chronic form involves long-term productive cough.

bronchoconstriction

The narrowing of the airways due to contraction of smooth muscle.

bronchospasm

A sudden, involuntary contraction of the smooth muscle in the walls of the bronchi.

chronic obstructive pulmonary disease (COPD)

A progressive lung disease characterized by chronic obstruction of airflow (includes emphysema and chronic bronchitis).

emphysema

A lung condition marked by the destruction of alveolar walls, leading to loss of elasticity and air trapping.

hemoptysis

The coughing up of blood or blood-stained sputum from the respiratory tract.

pneumonia, pneumonitis

Inflammation of the lung tissue, typically where alveoli fill with exudate or fluid.

pulmonary embolism, embolism

The blockage of a pulmonary artery by a blood clot or other foreign material.

tracheomalacia

A softening of the tracheal cartilage, leading to airway collapse during expiration.

tracheostenosis

Abnormal narrowing of the trachea.

hemothorax

An accumulation of blood in the pleural cavity.

hydrothorax

An accumulation of watery fluid in the pleural cavity.

pneumothorax

The presence of air or gas in the pleural cavity, causing lung collapse.

pyothorax

An accumulation of pus in the pleural cavity.

apnea, apneic

The temporary cessation of breathing.

asphyxia

A condition of severe oxygen deprivation combined with increased carbon dioxide levels.

bradypnea, bradypneic

An abnormally slow rate of breathing.

dyspnea, dyspneic

Difficult, painful, or labored breathing; shortness of breath.

hyperventilation

Increased rate and depth of breathing, lowering blood carbon dioxide levels.

hypoventilation

Decreased rate or depth of breathing, causing blood carbon dioxide levels to rise.

orthopnea

Difficulty breathing when lying flat, relieved by sitting or standing up.