Respiratory System Lecture Notes

These vocabulary flashcards provide definitions and structural classifications of the respiratory system, including upper and lower tracts, breathing mechanisms, and common diseases, based on the course materials by Joan S. Awingan.

Conducting portion

The functional division of the respiratory system that transports air, including the nose, nasal cavity, pharynx, larynx, trachea, and bronchi through terminal bronchioles.

Respiratory portion

The functional division of the respiratory system responsible for gas exchange, consisting of respiratory bronchioles, alveolar ducts, and alveoli.

Breathing (pulmonary ventilation)

The movement of air in and out of the lungs consisting of inhalation (inspiration) and exhalation (expiration).

External respiration

The specific gas exchange process occurring between the external environment and the blood within the air sacs of the lungs.

Internal respiration

The gas exchange process occurring at the cellular level between the blood and the body's cells.

Vibrissae

Hairs located within the respiratory system that serve as a defense mechanism to filter air.

Nasal conchae

Structures that swirl air over the mucus membrane in the nasal cavity to filter, warm, and humidify the air.

Paranasal sinuses

Paired air spaces located in the frontal, ethmoidal, sphenoidal, and maxillary bones that decrease the weight of the skull and communicate with the nasal cavity.

Pharynx

A funnel-shaped tube extending from the internal nares to the larynx that is common to both the respiratory and digestive systems; commonly called the throat.

Nasopharynx

The superiormost region of the pharynx located posterior to the nasal cavity and superior to the soft palate where normally only air passes.

Pharyngeal tonsil

A single lymphatic organ located on the posterior nasopharynx wall, also commonly referred to as the adenoids.

Auditory tubes

Paired tubes in the lateral walls of the nasopharynx that connect the pharynx to the middle ear.

Oropharynx

The middle pharyngeal region located between the uvula and the top of the epiglottis that serves as a common pathway for both air and swallowed food/drink.

Laryngopharynx

The inferior, narrowed region of the pharynx connecting with both the esophagus and the larynx, lined with non-keratinized stratified squamous epithelium.

Larynx

A short, cylindrical airway known as the voice box that conducts air into the lower respiratory tract, produces sound, and prevents swallowed materials from entering the trachea.

Thyroid cartilage

The anterior portion of the larynx often referred to as the 'Adam's apple'.

Epiglottis

An upper leaf-shaped piece of cartilage that moves to cover the opening of the trachea during the process of swallowing.

Vocal folds

Inferior ligaments known as 'true vocal cords' that produce sound when air passes between them.

Vestibular folds

Superior ligaments known as 'false vocal cords' that have no function in sound production but protect the vocal folds.

Rima glottidis

The opening between the vocal folds.

Trachea

A flexible, slightly rigid tubular organ often called the 'windpipe' that is supported by $15$ to $20$ C-shaped tracheal cartilages.

Annular ligaments

Elastic sheets that connect the C-shaped cartilage rings of the trachea.

Carina

An internal ridge at the most inferior tracheal cartilage that separates the primary bronchi at their origin.

Right primary bronchus

The branch of the trachea that is shorter, wider, and more vertically oriented than the left, making it more likely for foreign particles to lodge there.

Secondary bronchi

Also called lobar bronchi, these are branches of the primary bronchi with one for each lobe of the lung ($2$ in the left lung, $3$ in the right lung).

Tertiary bronchi

Also called segmental bronchi, these supply specific parts of the lung known as bronchopulmonary segments.

Apex (cupola)

The relatively blunt superior region of the lung that projects slightly superior and posterior to the clavicle.

Tidal air

The amount of air that goes in and out of the lungs during normal breathing, which is approximately $500\,\text{cc}$.

Medulla oblongata

The specific part of the brain stem that controls respiratory movements.

Visceral pleura

The serous membrane that tightly covers the outer surface of each lung.

Parietal pleura

The serous membrane that lines the internal thoracic walls, lateral surfaces of the mediastinum, and the superior surface of the diaphragm.

Alveolar macrophages

Cells located within the alveoli that act as 'cleaners' for the respiratory system.

Surfactant

A substance secreted by specific cells in the alveoli that lowers surface tension and humidifies the sac.

External intercostals

Muscles that elevate the ribs during inhalation to increase the transverse dimensions of the thoracic cavity.

Internal intercostals

Muscles that depress the ribs only during forced exhalation.

Emphysema

A condition that may cause a loss of alveoli or their functionality, leading to shortness of breath and reduced gas exchange capacity.

Influenza (Flu)

A viral infection of the nose, throat, and sometimes lungs, characterized by fever, cough, and body aches.

Pneumonia

An infection caused by bacteria, viruses, or fungi that inflames the air sacs in one or both lungs.

Chronic Obstructive Pulmonary Disease (COPD)

A group of lung diseases, including chronic bronchitis and emphysema, characterized by breathing difficulties and excess mucus production.

Asthma

A chronic condition involving the inflammation and narrowing of the airways, causing wheezing and chest tightness.

Bronchitis

Inflammation of the lining of the bronchial tubes, often due to viral infections, leading to coughing and mucus production.