Learn about sickle cell anemia and blood behavior in sickle cell patients

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Learn about the human immune response phagocytosis by watching time-lapse photography of a leukocyte, or white blood cell (globular structure), consuming bacteria.

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In a circuit through the cardiovascular system, red blood cells transport oxygen from the lungs to the body tissues and transport carbon dioxide from the body tissues to the lungs.

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Learn about sickle cell anemia.

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Learn how blood donation works.

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Are you “red-y” to find out?

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And how much do you really need?

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There are two major protein complexes that transport cholesterol through the bloodstream: high-density lipoproteins (HDL) and low-density lipoproteins (LDL). Cholesterol attached to LDLs is primarily that which builds up in atherosclerotic deposits in the blood vessels; for this reason, LDL is often described as the “bad” form of cholesterol. HDLs, on the other hand, may actually serve to retard or reduce atherosclerotic buildup, and hence HDL is often referred to as the “good” form of cholesterol.

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The heart, located between the lungs, powers the circulatory system.