What Is Blood Made Of

What is blood made up of?

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Blood is made up of the following four components:

1.  Red blood cells.  These make up 40-50% of blood by volume.  Their function is to carry oxygen from the lungs to all parts of the body.

2.  White blood cells.  These make up only about 1% of a healthy person's blood by volume.  But they are very important in that they help rid the body of harmful organisms like bacteria.

3.  Platelets.  These are the part of blood that allows it to clot at the site of a wound.

4.  Plasma.  This is made up mostly of water.  It helps bring nutrients to the cells and to carry waste away from them.  About 55% of blood (by volume) is plasma.

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Blood is an essential part of your body (no duh, right?) It delivers oxygen and nutrients to the cells of the body and it also transports waste products away from the cells.

It is made up of blood cells suspended in a liquid called blood plasma. Plasma is about 55% of the fluid found in blood and is mostly water. Floating in the plasma are:

  • proteins,
  • hormones (help to regulate body activities like mood, sleep, growth, etc.)
  • glucose, (sugars for energy)
  • minerals,
  • carbon dioxide (which the body is trying to get rid of.)
  • platelets (for clotting if you are cut)
  • red blood cells (contain hemoglobin, which helps to move oxygen.)
  • white blood cells (help resist infections and deal with parasites.)

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