|
Your blood is made up of plasma, red blood cells, white blood cells and platelets.
Plasma
More than half of your blood is made of plasma. It’s a clear, yellow liquid which is mostly water. Plasma contains proteins and other substances that make the blood coagulate (thicken) when you cut yourself.
During the blood’s journey through the body (circulation), the plasma carries with it the nourishment that your body needs and it removes any waste your body wants to get rid of.
Red Blood Cells
There are millions of red blood cells floating around in the plasma. These carry oxygen from the lungs to all parts of the body, and they bring back carbon dioxide to the lungs where it is exhaled (breathed out). Red blood cells are created in your bone marrow, they only last a few months and so your bone marrow is always busy making new ones.
White Blood Cells
These are your body’s armed forces. Whenever dangerous bacteria or germs enter your body, the white blood cells rush there, surround, and kill them. New white blood cells (created in the bone marrow) replace those that die in the process.
Platelets
These prevent too much blood from running out when you cut yourself. They gather at the site of a wound and bind with substances in the plasma to form a layer that seals the wound, this layer dries and becomes a scab. Under the scab the skin heals and renews. After a while the scab will fall off, unless you pick it off first!
|