Respiratory System Lecture Flashcards

Comprehensive vocabulary flashcards covering the anatomy, physiology, and clinical conditions of the respiratory system as described in the lecture notes.

Aerobic metabolism

The primary method by which cells obtain energy; it requires oxygen and produces carbon dioxide.

Respiratory mucosa

A layer lining the conducting portion of the respiratory system consisting of an epithelium and an areolar tissue layer called the lamina propria.

Lamina propria

The areolar tissue layer of the respiratory mucosa; in the lower respiratory system, it contains smooth muscle cells that encircle the lumen of bronchioles.

Nasal vestibule

The space contained within the flexible tissues of the nose where nasal hairs trap large particles.

Nasal septum

The structure that divides the nasal cavity into left and right sides, with an anterior portion made of hyaline cartilage.

Meatuses

Narrow passageways (superior, middle, and inferior) in the nasal cavity that produce air turbulence to trap particles and warm incoming air.

Choanae

The openings of the nasal cavity through which air flows into the nasopharynx.

Pharynx

A chamber shared by the digestive and respiratory systems divided into the nasopharynx, oropharynx, and laryngopharynx.

Glottis

A slit-like opening between the vocal cords through which air flows from the pharynx to the larynx.

Laryngeal prominence

The anterior surface of the thyroid cartilage, commonly known as the Adam’s apple.

Epiglottis

A flap of elastic cartilage that covers the glottis during swallowing to prevent food and liquids from entering the respiratory tract.

Phonation

The process of sound production at the larynx.

Articulation

The modification of sound using the lips, tongue, and teeth to produce speech.

Trachealis muscle

The muscle that connects the ends of each C-shaped tracheal cartilage, allowing for distortion of the tracheal wall during swallowing.

Carina of trachea

A ridge that separates the openings of the right and left main bronchi at their junction with the trachea.

Bronchodilation

The enlargement of the luminal diameter of the airway caused by sympathetic activation.

Bronchoconstriction

The reduction of the luminal diameter of the airway caused by parasympathetic activation or histamine release.

Pneumocytes type I

Thin, delicate simple squamous epithelial cells that form the alveolar cell layer and serve as the site of gas exchange.

Pneumocytes type II

Specialized alveolar cells that produce surfactant, an oily secretion that reduces surface tension.

Blood air barrier

The three-layer structure consisting of the alveolar cell layer, capillary endothelial layer, and fused basement membrane where gas exchange occurs.

Cardiac notch

An indentation on the medial margin of the left lung.

Hilum

The region where pulmonary vessels, nerves, and lymphatics enter the lung.

Pulmonary embolism

A condition where a blocked branch of the pulmonary artery stops blood flow to lobules or alveoli.

Hypoxia

A condition characterized by low tissue oxygen levels.

Anoxia

A dangerous condition involving a complete lack of oxygen in tissues.

Boyle’s law

The physical law defining the inverse relationship between gas pressure and volume, expressed as $P = 1/V$.

Eupnea

Also known as quiet breathing, it involves active inhalation and passive exhalation.

Hyperpnea

Also known as forced breathing, it involves active inhalation and active exhalation assisted by accessory muscles.

Intrapulmonary pressure

Also called intra-alveolar pressure, it is the pressure inside the respiratory tract; the difference from atmospheric pressure determines airflow direction.

Pneumothorax

The entry of air into the pleural cavity, which can result in atelectasis or a collapsed lung.

Tidal volume ($V_T$)

The amount of air moved into or out of the lungs during a single breath.

Vital capacity

The sum of the expiratory reserve volume, tidal volume, and inspiratory reserve volume.

Dalton’s law

The principle stating that each gas in a mixture contributes to the total pressure in proportion to its relative abundance.

Henry’s law

The law stating that at a given temperature, the amount of a gas in solution is proportional to the partial pressure of that gas.

Bohr effect

The effect of $pH$ on the hemoglobin saturation curve, where a drop in $pH$ causes more oxygen to be released.

Chloride shift

The exchange of bicarbonate ions moving into the plasma for $Cl^{-}$ ions entering the red blood cell.

Dorsal respiratory group (DRG)

The inspiratory center in the medulla oblongata that functions in both quiet and forced breathing.

Pneumotaxic centers

Nuclei in the pons that inhibit the apneustic centers and promote passive or active exhalation to modify the respiratory rate.

Hypercapnia

An increase in arterial $PCO_2$ often caused by hypoventilation.

Hering-Breuer reflexes

Two reflexes (inflation and deflation) involved in forced breathing to prevent overexpansion and regulate inspiration.