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Biology

Hematopoiesis: The Formation of Blood Cells

Quick fact

An adult human produces about 2.5 billion red blood cells, 2.5 billion platelets, and 1 billion white blood cells per kilogram of body weight every day.

Why this is interesting

Every second, your body produces millions of new blood cells. But where do they all come from, and how does your body decide which type to make?