functions of blood

Question 1

What are the four main functions of blood?

Answer 1

1. Transport food, waste products and hormones by plasma.
2. Transport of heat from internal organs by plasma (helps maintain constant body temp).
3. Transport of oxygen by red blood cells.
4. Defence against disease.

Question 2

The function of blood is to defend against disease. What is this due to? (3)

Answer 2

1. White blood cells (phagocytes), which engulf and digest bacteria.
2. Lymphocytes, which produce antibodies to destroy foreign bodies.
3. Platelets slotting the blood, which prevents blood loss and the entry of disease-causing organisms.