1. What is the main function of the respiratory system? a) Digestion b) Breathing c) Circulation d) Excretion

2. Which organ pumps blood throughout the body? a) Brain b) Stomach c) Heart d) Liver

3. Where does the process of digestion begin? a) Stomach b) Mouth c) Intestine d) Esophagus

4. What is the largest organ in the human body? a) Heart b) Liver c) Skin d) Brain

5. Which type of blood vessel carries blood away from the heart? a) Veins b) Arteries c) Capillaries d) Lymphatic vessels

6. What is the main function of red blood cells? a) Fight infections b) Clot blood c) Carry oxygen d) Digest food

7. Which part of the brain controls balance and coordination? a) Cerebrum b) Cerebellum c) Brainstem d) Medulla

8. What is the basic unit of the nervous system? a) Neuron b) Muscle fiber c) Bone cell d) Blood cell

9. Which organ filters waste from the blood to form urine? a) Liver b) Kidney c) Bladder d) Pancreas

10. What substance in the blood helps to clot and stop bleeding? a) Plasma b) Platelets c) Red blood cells d) White blood cells

11. What is the main function of the large intestine? a) Absorb nutrients b) Absorb water c) Produce enzymes d) Filter toxins

12. Which hormone regulates blood sugar levels? a) Thyroxine b) Adrenaline c) Insulin d) Estrogen

13. What is the main function of the skeletal system? a) Produce blood cells b) Provide support and structure c) Regulate body temperature d) Absorb nutrients

14. Which part of the digestive system is responsible for nutrient absorption? a) Stomach b) Small intestine c) Large intestine d) Esophagus

15. Which organ produces bile to help digest fats? a) Pancreas b) Gallbladder c) Liver d) Stomach