ANIMAL PHYSIOLOGY
HUMAN CIRCULATION
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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Air breathed in has less oxygen than air breathed out.
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Alveoli have thick walls and a large surface area.
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Alveoli have thin walls and a large surface area.
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The concentration of oxygen in the blood is higher than in the alveoli.
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Detailed explanation-1: -The layer of moisture in the alveoli allows gases to dissolve so that they can diffuse quickly. The alveoli have a very large total surface area and a very good blood supply, provided by the dense network of capillaries that surround them.
Detailed explanation-2: -Hemoglobin (Heme + Globin) The protein hemoglobin is a molecule which is responsible for carrying almost all of the oxygen in the blood. It is composed of four subunits, each with a heme group plus a globin chain.
Detailed explanation-3: -In a process called diffusion, oxygen moves from the alveoli to the blood through the capillaries (tiny blood vessels) lining the alveolar walls. Once in the bloodstream, oxygen gets picked up by the hemoglobin in red blood cells.
Detailed explanation-4: -Each alveolus is very closely associated with a network of capillaries containing deoxygenated blood from the pulmonary artery. The capillary and alveolar walls are very thin, allowing rapid exchange of gases by passive diffusion along concentration gradients.
Detailed explanation-5: -The alveoli cover a surface of more than 1, 399 feet (ft) or 130 square meters (m2) . This large surface area is necessary to process the huge amounts of air involved in breathing and getting oxygen to your lungs.