1. What is the primary function of red blood cells in the human body?
a) Fighting infections
b) Carrying oxygen
c) Producing hormones
d) Clotting blood
Answer: b) Carrying oxygen
2. Which vitamin is essential for maintaining healthy vision?
a) Vitamin A
b) Vitamin C
c) Vitamin D
d) Vitamin E
Answer: a) Vitamin A
3. What is the basic unit of life in all living organisms?
a) Tissue
b) Organ
c) Cell
d) Atom
Answer: c) Cell
4. Which organ is responsible for filtering waste from the blood in the human body?
a) Liver
b) Lungs
c) Kidneys
d) Heart
Answer: c) Kidneys
5. What type of macronutrient is primarily used by the body for energy?
a) Proteins
b) Carbohydrates
c) Fats
d) Vitamins
Answer: b) Carbohydrates
6. Which hormone regulates blood sugar levels in the human body?
a) Insulin
b) Adrenaline
c) Thyroxine
d) Melatonin
Answer: a) Insulin
7. What is the main structural component of plant cell walls?
a) Cellulose
b) Starch
c) Protein
d) Chitin
Answer: a) Cellulose
8. Which process in plants converts sunlight into chemical energy?
a) Respiration
b) Photosynthesis
c) Fermentation
d) Transpiration
Answer: b) Photosynthesis
9. Which blood group is known as the universal donor?
a) A
b) B
c) AB
d) O
Answer: d) O
10. Which part of the brain is responsible for controlling voluntary muscle movements?
a) Cerebellum
b) Medulla
c) Cerebrum
d) Hypothalamus
Answer: c) Cerebrum
11. What is the primary function of white blood cells?
a) Transporting oxygen
b) Producing enzymes
c) Fighting infections
d) Clotting blood
Answer: c) Fighting infections
12. Which organ in the human body produces bile?
a) Stomach
b) Liver
c) Pancreas
d) Small intestine
Answer: b) Liver
13. Which type of fat is considered healthy and is found in foods like avocados and olive oil?
a) Saturated fat
b) Trans fat
c) Monounsaturated fat
d) Polyunsaturated fat
Answer: c) Monounsaturated fat
14. What is the main function of hemoglobin in the blood?
a) Clotting blood
b) Carrying oxygen
c) Fighting infections
d) Regulating temperature
Answer: b) Carrying oxygen
15. Which vitamin is essential for the absorption of calcium in the body?
a) Vitamin A
b) Vitamin B12
c) Vitamin C
d) Vitamin D
Answer: d) Vitamin D
16. What is the primary function of the digestive system?
a) Circulating blood
b) Breaking down food and absorbing nutrients
c) Regulating hormones
d) Protecting against infections
Answer: b) Breaking down food and absorbing nutrients
17. Which enzyme is responsible for breaking down starch into sugar in the human body?
a) Pepsin
b) Lipase
c) Amylase
d) Trypsin
Answer: c) Amylase
18. What is the main purpose of the human immune system?
a) Transporting oxygen
b) Producing energy
c) Defending the body against pathogens
d) Regulating body temperature
Answer: c) Defending the body against pathogens
19. Which vitamin is crucial for blood clotting?
a) Vitamin A
b) Vitamin K
c) Vitamin E
d) Vitamin B6
Answer: b) Vitamin K
20. What is the process by which plants lose water vapor through their leaves?
a) Photosynthesis
b) Respiration
c) Transpiration
d) Fermentation
Answer: c) Transpiration