Blood
Blood is about 55% plasma, a yellowish liquid that is mostly water and carries dissolved food, salts, wastes and proteins, and about 45% cells made in the bone marrow. Red cells, the most numerous, are dimpled discs with no nucleus, full of iron-containing haemoglobin that picks up oxygen in the lungs; too little iron causes anaemia. White cells are bigger, have a nucleus and defend the body against germs. Platelets are tiny cell fragments that, with plasma proteins, make a clot to stop bleeding.
Depth 1 · Foundation
You can name the parts of blood, from plasma to platelets, say what each does, and explain why iron matters for red cells.
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Foundation
You can name the parts of blood, from plasma to platelets, say what each does, and explain why iron matters for red cells.
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