Blood is the life-maintaining fluid that circulates through the body’s heart, arteries, veins and capillaries.

The blood performs two major functions:
It transports:

• Oxygen and carbon dioxide
• Food molecules (glucose, lipids, amino acids, vitamins)
• Hormones and signalling tissue damage
• Heat and regulating core body temperature
• Ions (eg Na+, HCO3)

through the body.
It removes infections and other foreign materials, and protects the body from them.