What blood is made of
Blood is a liquid connective tissue that flows through the vessels.
Blood left to stand
If blood is kept from clotting and left to stand, it separates: a pale yellow liquid, the plasma (about 55%), on top of the blood cells (about 45%).
Red blood cells
Carry oxygen
White blood cells
Defend the body
Platelets
Help blood clot
What blood does
- Carries oxygen, carbon dioxide, digested food, waste and hormones
- Spreads heat and keeps body temperature steady
- Defends the body against germs
- Clots to stop bleeding