Loading…
Logo Medical Art Library

02 Transport and Gas Exchange

ID: ANM11027
MEDICAL ANIMATION TRANSCRIPT: The respiratory system regulates oxygen and carbon dioxide levels within the blood. Respiration includes ventilation, gas exchange between the air, blood, and tissues within the body, and the use of oxygen for metabolism. Inhalation allows oxygen to enter the body, pulling air into the nose and mouth, lungs, and into the air sacs called alveoli, where gas exchange takes place. Alveoli move freely when air is inhaled and exhaled. Capillaries are small blood vessels that line the walls of the alveoli. During gas exchange, oxygen enters and carbon dioxide exits the bloodstream via the alveolar-capillary membrane. Once oxygen molecules move from the alveoli into the capillaries, they dissolve into the plasma and enter the red blood cell or erythrocyte. Erythrocytes contain millions of soluble proteins called hemoglobin. Hemoglobin contains four subunits each capable of binding one molecule of oxygen. Once one molecule of oxygen binds to one of the subunits, the other sites bind oxygen more readily. Dissolved and bound oxygen flows through the arterial bloodstream to capillaries within tissues. Upon arrival, carbon dioxide loading of the erythrocyte promotes oxygen unloading. Oxygen metabolism within cells produces carbon dioxide gas as a metabolic waste. Carbon dioxide exits the cells and tissues and is converted into bicarbonate within the erythrocytes. Converting carbon dioxide to bicarbonate releases hydrogen ions that decrease oxygen affinity for hemoglobin, freeing the oxygen to be delivered to tissue cells. After delivering oxygen to the tissues, the carbon dioxide-rich blood returns to the lungs through the venous circulation and then to the pulmonary artery. Inside each erythrocyte, the bicarbonate conversion is reversed, recreating carbon dioxide, which diffuses across the erythrocyte into the alveoli and lungs and is excreted out of the body. ♪ [music] ♪
Variations
    (none available)

Nucleus Medical Media Disclaimer of Medical and Legal Liability

Nucleus Medical Media ("Nucleus") does not dispense medical or legal advice, and the text, illustrations, photographs, animations and other information ("Content") available on this web site is for general information purposes only. As with any medical or legal issue, it is up to you to consult a physician or attorney for professional advice. YOU SHOULD NOT DISREGARD PROFESSIONAL MEDICAL OR LEGAL ADVICE BASED ON CONTENT CONTAINED ON THIS WEB SITE, NOR SHOULD YOU RELY ON THE CONTENT ON THIS WEB SITE IN PLACE OF PROFESSIONAL MEDICAL OR LEGAL ADVICE.

NUCLEUS DISCLAIMS ALL RESPONSIBILITY AND LIABILITY FOR ANY COUNSEL, ADVICE, TREATMENT, DIAGNOSIS OR ANY MEDICAL, LEGAL OR OTHER INFORMATION, SERVICES OR PRODUCTS THAT YOU OBTAIN BASED ON VIEWING THE CONTENT OF THIS SITE. THE INFORMATION ON THIS WEB SITE SHOULD NOT BE CONSIDERED COMPLETE OR SUITABLE FOR ANY PURPOSE WHATSOEVER.

Mature Content Disclaimer: Certain Content on this web site contains graphic depictions or descriptions of medical information, which may be offensive to some viewers. Nucleus, its licensors, and its suppliers disclaim all responsibility for such materials.

close