Introduction to the Respiratory System

Vocabulary flashcards covering the anatomy, physiology, gas exchange mechanisms, protective reflexes, infectious diseases, and pulmonary disorders of the human respiratory system.

Conducting Airways

The respiratory structures primarily involved in ventilation that change the quality of atmospheric air, comprising the upper respiratory tract (nose, mouth, pharynx, larynx, trachea) and the bronchi.

Respiratory Airways

The structures where gas exchange takes place, consisting of lobules (bronchioles, arteriole, pulmonary capillaries, veins) and alveoli.

Mucociliary Escalator

A respiratory defense mechanism in which goblet cells produce mucus to trap foreign substances, and cilia move the mucus and trapped particles upward toward the throat for swallowing.

Trachea

The main conducting airway into the lungs that bifurcates into the primary bronchi.

Cough Reflex

A central nervous system reflex initiated by stimulation of receptors in the sensitive walls of the trachea and conducting bronchi, which pushes air through the bronchial tree under high pressure to clear irritants.

Sneeze Reflex

A protective respiratory reflex initiated by the stimulation of sensory receptors located in the nasal cavity.

Bronchial Tube Layers

The structural tissue layers comprising the walls of the bronchial tubes: cartilage, muscle, and epithelial cells.

Alveoli

The smallest functional units of the lungs consisting of microscopic respiratory sacs at the ends of bronchioles where gas exchange occurs.

Lobes of the Lungs

The anatomical divisions of the lungs, consisting of two lobes in the left lung and three lobes in the right lung.

Respiratory Membrane

The anatomical barrier across which gas exchange occurs, consisting of six layers: capillary endothelium, capillary basement membrane, interstitial space, alveolar basement membrane, alveolar epithelium, and the surfactant layer.

Surfactant

A lipoprotein substance lining the alveoli that reduces surface tension, enabling the alveolar sacs to open for gas exchange.

Ventilation

The mechanical movement of air controlled by the central nervous system, specifically the respiratory centers in the pons and medulla.

Chemoreceptors (Respiratory)

Sensory receptors that detect elevated levels of acid or carbon dioxide, triggering an immediate increase in the rate and/or depth of respiration.

Vagus Nerve (Respiratory Action)

The cranial nerve responsible for stimulating diaphragm contraction to initiate inspiration.

Common Cold

An upper respiratory viral invasion of tissues that triggers histamine and prostaglandin release, producing an inflammatory response with symptoms like sinus pain, nasal congestion, runny nose, sneezing, watery eyes, scratchy throat, and headache.

Seasonal Rhinitis

Inflammation of the nasal cavity and upper airways in response to a specific antigen, causing vigorous inflammation, nasal congestion, sneezing, stuffiness, and watery eyes.

Sinusitis

Inflammation of the epithelial lining of the sinus cavities that causes severe pain due to pressure against bone; untreated infections may travel to brain tissue or compromise vision.

Pneumonia

Inflammation of the lungs caused by bacterial or viral infection or aspiration of foreign materials, manifesting with localized swelling, engorgement, exudation of protective sera, difficulty breathing, fatigue, fever, and noisy breath sounds.

Tuberculosis

An infectious respiratory disorder characterized by a cough (often bloody-tinged), fatigue, shortness of breath, fever, chills, night sweats, and weight loss.

Atelectasis

The incomplete expansion or collapse of alveoli caused by outside pressure, pleural effusion, or airway obstruction, presenting with crackles, dyspnea, fever, cough, and hypoxia.

Bronchiectasis

A chronic pulmonary disease characterized by permanent dilation of the bronchial tree alongside chronic infection and inflammation, presenting with fever, malaise, myalgia, arthralgia, and purulent, productive cough.

Asthma

A chronic inflammatory disorder of the airways marked by cytokine-mediated inflammation, reversible bronchospasm, mucosal edema, mucus production, and airway hyperactivity, presenting with wheezing, dyspnea, chest tightness, or cough.

Chronic Obstructive Pulmonary Disease (COPD)

A progressive, not completely reversible airflow limitation on expiration often caused by cigarette smoking, encompassing emphysema and chronic bronchitis, leading to increased lung inflation and impaired gas exchange.

Cystic Fibrosis

A hereditary disease involving epithelial linings of the respiratory, gastrointestinal, and reproductive tracts, characterized by thick, copious secretions that block airways and lead to recurrent infections and lung tissue destruction.

Respiratory Distress Syndrome (RDS)

A condition that causes obstruction at the alveolar level, frequently seen in premature infants born with low surfactant levels, resulting in impaired gas exchange and hypoxia.

Acute Respiratory Distress Syndrome (ARDS)

A severe disorder resulting from a major body insult, characterized by progressive loss of lung compliance, severe hypoxia, extensive epithelial cell damage, and increased permeability of the alveolar-capillary membrane.