Respiratory System Vocabulary

Flashcards of key vocabulary and definitions from the lecture notes on the respiratory system.

Respiration

The exchange of gases between the atmosphere, blood, and cells; takes place in ventilation, external respiration, and internal respiration.

Respiratory System

Consists of the nose, pharynx, larynx, trachea, bronchi, and lungs.

Upper Respiratory System

Nose, pharynx, and associated structures.

Lower Respiratory System

Larynx, trachea, bronchi, and lungs.

Conducting System

Nose, pharynx, larynx, trachea, bronchi, bronchiole, and terminal bronchioles; conducts air into the lungs.

Respiratory Portion

Respiratory bronchioles, alveolar ducts, alveolar sacs, and alveoli; area where gas exchange occurs.

Otorhinolaryngology

Branch of medicine dealing with the diagnosis and treatment of diseases of the ear, nose, and throat.

Rhinoplasty

Surgical procedure in which the structure of the external nose is altered for cosmetic or functional reasons.

Pharynx

Muscular tube lined by a mucous membrane; also known as the throat.

Nasopharynx

Anatomic region of the pharynx that functions in respiration.

Tonsillectomy

The surgical removal of the tonsils.

Larynx

Passageway that connects the pharynx with the trachea; also known as the voice box.

Vocal cords

Vocal folds that produce sound when vibrated.

Laryngitis

Inflammation of the larynx, usually caused by respiratory infection or irritants.

Trachea

Anterior to the esophagus; extends from the larynx to the primary bronchi; also known as the windpipe.

Pulmonary Bronchi

The trachea divides into the right and left of these.

Bronchial Tree

Consists of the trachea, primary bronchi, secondary bronchi, tertiary bronchi, bronchioles, and terminal bronchioles.

Lungs

Paired organs in the thoracic cavity; enclosed and protected by the pleural membrane.

Parietal Pleura

Outer layer of the pleural membrane, attached to the wall of the thoracic cavity.

Visceral Pleura

Inner layer of the pleural membrane, covering the lungs themselves.

Pneumothorax

Filling of the pleural cavity with air.

Lobules

Small compartments of the lungs that contain lymphatics, arterioles, venules, terminal bronchioles, respiratory bronchioles, alveolar ducts, alveolar sacs, and alveoli.

Alveolar Walls

Consist of type I alveolar cells, type II alveolar cells, and alveolar macrophages (dust cells).

Type II Alveolar Cells

Secrete alveolar fluid, which keeps the alveolar cells moist and contains surfactant.

Surfactant

Lowers the surface tension of alveolar fluid, preventing the collapse of alveoli with each expiration.

Alveolar-capillary membrane

Gas exchange occurs across this.

Ventilation – Perfusion Coupling

Vasoconstriction in response to hypoxia diverts pulmonary blood from poorly ventilated areas to well ventilated areas.

Inhalation (Inspiration)

Bringing air into the lungs.

Exhalation (Expiration)

Movement of air out of the lungs.

Compliance

Ease with which the lungs and thoracic wall can be expanded.

Eupnea

Normal variation in breathing rate and depth.

Apnea

Holding breath.

Dyspnea

Painful or difficult breathing.

Tachypnea

Rapid breathing rate.

Diaphragmatic breathing

Usual mode of operation to move air by contracting and relaxing the diaphragm to change the lung volume.

Spirometer (Respirometer)

Instrument used to measure air volumes exchanged during breathing and rate of ventilation.

Spirogram

Record from a spirometer.

Tidal Volume

Pulmonary air volume of 500 ml.

Minute Volume of Respiration

The total volume of air taken in during one minute (tidal volume x 12 respirations per minute = 6000 ml/min).

Dalton’s Law

Each gas in a mixture of gases exerts its own pressure as if all the other gases were not present.

Henry’s Law

The quantity of a gas that will dissolve in a liquid is proportional to the partial pressure of the gas and its solubility coefficient, when the temperature remains constant.

Hyperbaric Oxygenation

Technique that uses pressure to cause more oxygen to dissolve in the blood; used to treat anaerobic bacterial infections.

Internal (Tissue) Respiration

Exchange of gases between tissue blood capillaries and tissue cells; results in the conversion of oxygenated blood into deoxygenated blood.

Oxygen Transport

Carried with hemoglobin (Hb) inside red blood cells as oxyhemoglobin (HbO2).

Hemoglobin

Consists of a protein portion called globin and a pigment called heme.

PO2

Most important factor that determines how much oxygen combines with hemoglobin.

Respiratory Center

Area of the brain from which nerve impulses are sent to respiratory muscles; located bilaterally in the reticular formation of the brain stem.

Medullary Rhythmicity Area

Located in the medulla oblongata that controls the basic rhythm of respiration.

Pneumotaxic Area

Assists in coordinating the transition between inspiration and expiration; located in the upper pons.

Apneustic Area

Send impulses to the inspiratory area that activate it and prolong inspiration, inhibiting expiration.

Central Chemoreceptors

Located in the medulla oblongata; monitor levels of CO2 and O2 and provide input to the respiratory center.

Peripheral Chemoreceptors

Located in the walls of systemic arteries; monitor levels of CO2 and O2 and provide input to the respiratory center.

Hypercapnia

Slight increase in PCO2 (and thus H+).

Hypocapnia

Arterial PCO2 is lower than 40 mm Hg.

Hypoxia

Oxygen deficiency at the tissue level.

Hypoxic Hypoxia

Low PO2 in arterial blood.

Anemic Hypoxia

Too little functioning hemoglobin in the blood.

Stagnant Hypoxia

Inability of blood to carry oxygen to tissues fast enough to sustain their needs.

Histotoxic Hypoxia

Blood delivers adequate oxygen to the tissues, but the tissues are unable to use it properly.

Spasms of smooth muscle in bronchial tubes that result in partial or complete closure of air passageways; inflammation; inflated alveoli; and excess mucus production.

Asthma

Characterized by chronic and recurrent obstruction of air flow, which increases airway resistance.

Chronic obstructive pulmonary disease (COPD)

An inflammation of the bronchial tubes, the main symptom of which is a productive (raising mucus or sputum) cough.

Bronchitis

Bronchial epithelial cells are replaced by cancer cells after constant irritation has disrupted the normal growth, division, and function of the epithelial cells.

Bronchogenic carcinoma (lung cancer)

An acute infection of the alveoli.

Pneumonia

An inflammation of pleurae and lungs produced by the organism Mycobacterium tuberculosis.

Tuberculosis (TB)

An abnormal accumulation of interstitial fluid in the interstitial spaces and alveoli of the lungs.

Pulmonary edema

An inherited disease of secretory epithelia that affects the respiratory passageways, pancreas, salivary glands, and sweat glands.

Cystic fibrosis

Result from inhalation of asbestos particles.

Asbestos-related diseases

Sudden death of an apparently healthy infant, usually occurring during sleep.

Sudden Infant Death Syndrome

A form of respiratory failure characterized by excessive leakiness of respiratory membranes and severe hypoxia.

Acute respiratory distress syndrome