Composition of Blood

Question 2

Platelets

Answer 2

<1%

Assist the repair process following injury
- Contain chemical that promotes vascular spasm and clotting by forming a plug

Between 150000 and 400000 platelets in one microlitre of blood

Question 3

Leucocytes

Answer 3

White Blood Cells (WBC)

<1%

Primarily involved in the immune system
- Defends the body against invasion by pathogens and removes toxins, waste and abnormal or damaged cells.

Between 50000 and 100000 per microlitre of blood
- Mostly within connective tissue, organs and lymphatic system

Question 4

Erythrocytes

Answer 4

Red Blood Cells (RBC)

40-45%

Primarily transport O2 and CO2
Haemoglobin binds and transports O2 and CO2

Adult male - 4.5 - 6.5 Million RBC per microlitre of blood

Adult Female - 4.2 - 5.5 Million RBC per microlitre of blood

One drop of blood contains ≈ 260 Million RBCs

Question 5

Blood vessel content

Answer 5

• RBC
• WBC
• Platelets
  
  • All Suspended in plasma