The Respiratory System

Flashcards for the respiratory system, covering anatomy and physiology.

Respiratory functions

Provides oxygen to body tissues and removes carbon dioxide.

Physiologic divisions of the respiratory system

Includes the conducting and exchange (respiratory) zones.

Conducting division of the respiratory system

Provides a route for incoming and outgoing air, removes debris and pathogens, and warms/humidifies incoming air.

External nose

Mostly cartilage and soft tissue with two openings called nares/nostrils.

Internal nose

Opens into an expanded cavity (vestibule).

Nasal septum

Separates the right and left halves of the internal nose.

Conchae

Further divide up the nasal cavity to help make airflow less of a straight shot.

Nasopharynx

Airway only; contains pharyngeal tonsils.

Oropharynx

Passageway for air and food; contains palatine & lingual tonsils.

Laryngopharynx

Opens into the larynx anteriorly and esophagus posteriorly.

Glottis

Opening into the larynx; closed by the epiglottis when swallowing.

True vocal cords

Below the vestibular folds (false vocal cords).

Upper respiratory tract

All respiratory structures above the vocal cords.

Lower respiratory tract

All respiratory structures below the vocal cords.

Trachea

Branches into bronchi, creating the bronchial tree.

Bronchioles

Small bronchi.

Respiratory zone: Bronchioles

Lead to alveoli, which are sac-like structures bounded by a single layer of epithelium.

Respiratory membrane

Two thin epithelial layers (of alveoli and capillaries) where oxygen and carbon dioxide move across.

Type I cells

The main alveolar cells, simple squamous epithelium, containing ACE receptors.

Type II cells

Secrete surfactant to reduce sticking together of wet alveoli.

Alveolar macrophages

Phagocytic (immune) cells that remove debris and pathogens.

Visceral pleura

Inner layer that touches the lungs.

Parietal pleura

Outer layer of the pleura.

Ventilation

Moves air in and out of the lungs (alveoli).

Diaphragm

Major muscle of respiration.

Quiet breathing

Contraction of external intercostals and diaphragm for inspiration, relaxation for expiration.

Inspiration

Air enters the lungs.

Expiration

Air leaves the lungs.