Respiratory System Practice Flashcards

Vocabulary flashcards covering the structural plan, organs, ventilation mechanics, lung volumes, and breathing patterns of the respiratory system as described in Chapter 15 of Patton's Structure & Function of the Body.

Alveoli

Microscopic sacs enclosed by networks of capillaries that serve as the site for gas exchange, comparable to the leaves of an inverted tree.

Diffusion

The passive transport process responsible for the exchange of gases that occurs during respiration.

Upper respiratory tract

The division of the respiratory system composed of the nose, pharynx, and larynx.

Lower respiratory tract

The division of the respiratory system composed of the trachea, bronchial tree, and lungs.

Respiratory mucosa

A specialized membrane lining the air distribution tubes that produces more than $125\,mL$ of mucus each day to form a "mucous blanket."

Mucous blanket

A layer of mucus that serves as an air purification mechanism by trapping inspired irritants such as dust and pollen.

Nasal septum

A structure that separates the interior of the nose into two cavities.

Paranasal sinuses

Frontal, maxillary, sphenoidal, and ethmoidal cavities that drain into the nose.

Pharynx

A structure about $12.5\,cm$ ($5\,inches$) long that serves as a passageway for food, liquids, and air.

Nasopharynx

The upper portion of the pharynx where the pharyngeal tonsils and openings of the auditory tubes are located.

Larynx

The voice box, which contains the vocal cords and is formed by several pieces of cartilage, including the thyroid cartilage.

Thyroid cartilage

The largest piece of cartilage forming the larynx framework, also known as the Adam’s apple.

Epiglottis

A structure that partially covers the opening into the larynx.

Trachea

A tube about $11\,cm$ ($4.5\,inches$) long extending from the larynx into the thoracic cavity, held open by C-shaped rings of cartilage.

Bronchioles

Small branches of the bronchial tree that end in clusters of microscopic alveolar sacs.

Surfactant

A substance produced by type II cells in the alveoli that lines the alveolar surface.

Apex

The narrow upper part of each lung located under the collarbone.

Base

The broad lower part of each lung that rests on the diaphragm.

Pleura

A moist, smooth, slippery membrane that lines the chest cavity (parietal) and covers the outer surface of the lungs (visceral) to reduce friction.

External respiration

The process involving pulmonary ventilation (breathing) and pulmonary gas exchange.

Internal respiration

The process involving systemic gas exchange and cellular respiration.

Inspiration

The active process of moving air into the lungs, involving the contraction of the diaphragm and external intercostals.

Expiration

The movement of air out of the lungs, which is ordinarily a passive process aided by the elastic recoil of lung tissues.

Spirometer

A device used to measure the amount of air exchanged during breathing.

Tidal volume

The amount of air ($500\,mL$) taken into the lungs during normal inspiration and expelled during normal expiration.

Vital capacity

The largest amount of air that can be inhaled deeply and exhaled fully.

Expiratory reserve volume (ERV)

The amount of air that can be forcibly exhaled after expiring the tidal volume.

Inspiratory reserve volume (IRV)

The amount of air that can be forcibly inspired over and above a normal inspiration.

Respiratory control centers

The inspiratory and expiratory centers located in the medulla that regulate the normal rate of breathing ($12$ to $18$ breaths a minute).

Chemoreceptors

Sensors located in the carotid and aortic bodies that respond to changes in carbon dioxide, oxygen, and blood acid levels.

Eupnea

The term for normal breathing.

Hyperventilation

Rapid and deep respirations.

Hypoventilation

Slow and shallow respirations.

Dyspnea

Labored or difficult respirations.

Apnea

The temporary cessation or stoppage of respiration.

Respiratory arrest

The failure to resume breathing after a period of apnea.

Oxyhemoglobin

The compound formed when hemoglobin combines with oxygen in the lung capillaries.

Carbaminohemoglobin

The compound formed when hemoglobin combines with carbon dioxide for transport in the blood.