The respiratory system, which consists of the airway, the lungs and the muscles of respiration, works with the cardiovascular system to oxygenate blood and eliminate carbon dioxide. The two primary processes involved in respiration are ventilation and gas exchange. Ventilation is to the movement of gas through the airway to and from the lungs. Gas exchange refers to the passive exchange by diffusion of oxygen and carbon dioxide between pulmonary alveoli and blood in the pulmonary capillaries. Ventilation occurs under the control of the autonomic nervous system in coordination with the medulla oblongata and the pons in the brainstem, the areas of the brain constituting the respiration regulatory center.
The Respiratory System Images
Conceptual Vocabulary Self-Test
Basic Terms Crossword Puzzle
Basic Puzzle Solution
Conceptual Vocabulary for The Respiratory System
The respiratory system consists of the airways, the lungs, and the muscles that mediate the movement of air into and out of the body.
In humans the respiratory tract is the part of the anatomy that has to do with the process of respiration.
The larynx, colloquially known as the voicebox, is an organ in the neck of mammals involved in protection of the trachea and sound production.
The trachea, or windpipe, is a tube that extends from the larynx to the primary bronchi.
The diaphragm is a sheet of muscle extending across the bottom of the ribcage which separates the thoracic cavity from the abdominal cavity and performs an important function in respiration.
A nostril is one of the two channels of the nose, from the point where they bifurcate to the external opening.
A bronchus is a caliber of airway in the respiratory tract that conducts air into the lungs.
The right main bronchus is wider, shorter, and more vertical in direction than the left, entering the right lung nearly opposite the fifth thoracic vertebra.
The left main bronchus is smaller in caliber but longer than the right, entering the root of the left lung opposite the sixth thoracic vertebra.
The tertiary bronchi arise from the secondary bronchi.
The primary bronchioles arise from the tertiary bronchi.
Inhalation, also known as inspiration, is the movement of air from the external environment, through the airways, into the alveoli during breathing.
Exhalation, or expiration, is the movement of air out of the bronchial tubes, through the airways, to the external environment during breathing.
Pulmonary circulation is the portion of the cardiovascular system which carries oxygen-depleted blood away from the heart, to the lungs, and returns oxygenated blood back to the heart.
A terminal bronchiole is a bronchiole at the end of the conducting zone.
Alveolar ducts are the tiny end tubules of the branching airways that fill the lungs.
Vital capacity is the maximum volume of air that a person can exhale after maximum inhalation.
Functional residual capacity is the volume of air present in the lungs at the end of passive expiration.
Dead space is air that is inhaled by the body in breathing, but does not partake in gas exchange.
Pulmonary surfactant is a surface-active lipoprotein complex formed by type II alveolar cells which reduces surface tension in the air water interface within alveoli.
The nasal cavity, or nasal fossa, is a large air-filled space above and behind the nose in the middle of the face.
Each of the tertiary bronchi serves a specific bronchopulmonary segment, and each of these segments have their own artery.
A respiratory bronchiole is an airway at the beginning of the respiratory zone.
Ventilation rate is the rate at which gas enters or leaves the lung.
Pulmonary stretch receptors are mechanoreceptors found in the lungs, which when the lung expands, initate the Hering-Breuer reflex, reducing the respiratory rate.
The Hering-Breuer reflex is a reflex triggered to prevent overinflation of the lungs by pulmonary stretch receptors present in the smooth muscle of the airways which respond to excessive stretching of the lung.
Clara cells are non-mucous and non-ciliated secretory cells found in the primary bronchioles of the lungs.
The alveolar-capillary barrier exists in the gas exchanging region of the lungs, preventing air bubbles from forming in the blood and preventing blood from entering the alveoli.
Respiratory minute volume is the volume of air which can be inhaled or exhaled from a person's lungs in sixty seconds.
Lamellar bodies, or keratinosomes, are secretory organelles found in type II pneumocytes which deliver pulmonary surfactant after being released from the cell.
Spirometry is the most common of the Pulmonary Function Tests (PFTs), measuring lung function, specifically the measurement of the amount and/or speed of air that can be inhaled and exhaled.
A respirometer is a device used to measure the rate of respiration of a living organism by measuring its rate of exchange of oxygen and carbon dioxide.
Dipalmitoylphosphatidylcholine (DPPC) is a phospholipid and the major constituent of pulmonary surfactant.
Compliance is the ability of the lungs to stretch in a change in volume relative to an applied change in pressure.
The respiratory quotient is a unitless number used in calculations of basal metabolic rate when estimated from carbon dioxide production.
Diffusion capacity is a measurement of the lung's ability to transfer gases.
The WikiPremed MCAT Course is a comprehensive course in the undergraduate level general sciences. Undergraduate level physics, chemistry, organic chemistry and biology are presented by this course as a unified whole within a spiraling curriculum. Please read our policies on Privacy and Shipping & Returns. Contact Us. MCAT is a registered trademark of the Association of American Medical Colleges, which does not endorse the WikiPremed Course. WikiPremed offers the customers of our publications or our teaching services no guarantees regarding eventual performance on the MCAT.
WikiPremed is a trademark of Wisebridge Learning Systems LLC. The work of WikiPremed is published under a Creative Commons Attribution NonCommercial ShareAlike License. There are elements of work here, such as a subset of the images in the archive from WikiPedia, that originated as GNU General Public License works, so take care to follow the unique stipulations of that license in printed reproductions.