Answer:
Inside the air sacs, oxygen moves across paper-thin walls to tiny blood vessels called capillaries and into your blood. A protein called haemoglobin in the red blood cells then carries the oxygen around your body.
Explanation:
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B antigens are present on the cells
The hydraulic skeleton is composed of muscle and fluid.
First, deoxygenated blood flows into the right atrium of the heart from the inferior and superior vena cava.
Blood then flows through the bicuspid valve and into the right ventricle.
The blood then flows through the pulmonary valve and into the pulmonary artery. Arteries carry blood away from the heart while veins return blood to the heart. The pulmonary artery is on of the only arteries that carries deoxygenated blood.
Blood will then pass through the lungs and will be oxygenated.
After being oxygenated, the blood enters the pulmonary veins. The pulmonary veins are some of the only veins that carry oxygenated blood.
Blood enters back into the heart through the left atrium.
Then, blood flows into the left ventricle through the mitral valve.
Finally, blood is pumped through the aortic valve, into the aorta, and is distributed throughout the body.
4. all of the above is the answer
