1. What is homeostasis?
A) The process of maintaining a stable internal environment
B) The breakdown of food in the body
C) The movement of gases in and out of the lungs
D) The synthesis of proteins in the body
Answer: A) The process of maintaining a stable internal environment
2. Which of the following is NOT involved in maintaining homeostasis?
A) Hormonal regulation
B) Thermal regulation
C) Osmoregulation
D) Blood pressure regulation
Answer: D) Blood pressure regulation
3. The primary organ involved in regulating body temperature is:
A) Heart
B) Brain
C) Lungs
D) Skin
Answer: B) Brain
4. Which of the following is a key feature of homeostasis?
A) Inability to adapt
B) Regulation of internal conditions
C) Maximum energy consumption
D) Irregular function of body systems
Answer: B) Regulation of internal conditions
5. Which part of the brain is responsible for thermoregulation?
A) Medulla oblongata
B) Hypothalamus
C) Cerebrum
D) Cerebellum
Answer: B) Hypothalamus
6. What does the term ‘negative feedback’ refer to in homeostasis?
A) Amplification of the stimulus
B) Reduction of the stimulus
C) No response to stimuli
D) Constant increase in the stimulus
Answer: B) Reduction of the stimulus
7. Which process helps maintain the water balance in the body?
A) Respiration
B) Osmoregulation
C) Circulation
D) Protein synthesis
Answer: B) Osmoregulation
8. What is the main role of the kidneys in homeostasis?
A) Absorption of nutrients
B) Regulation of blood sugar levels
C) Regulation of water and salt balance
D) Oxygen transport
Answer: C) Regulation of water and salt balance
9. In humans, the body’s temperature is regulated to approximately:
A) 35°C
B) 37°C
C) 39°C
D) 40°C
Answer: B) 37°C
10. Which organ is responsible for controlling blood glucose levels?
A) Liver
B) Heart
C) Kidneys
D) Lungs
Answer: A) Liver
11. Insulin is secreted by which organ to regulate blood glucose levels?
A) Pancreas
B) Liver
C) Stomach
D) Small intestine
Answer: A) Pancreas
12. The process by which the body maintains its internal pH is known as:
A) Acid-base homeostasis
B) Osmoregulation
C) Thermoregulation
D) Excretion
Answer: A) Acid-base homeostasis
13. Which of the following systems is directly involved in the regulation of body temperature?
A) Circulatory system
B) Digestive system
C) Nervous system
D) Endocrine system
Answer: C) Nervous system
14. What is the role of the hypothalamus in maintaining homeostasis?
A) It regulates heartbeat
B) It releases hormones for growth
C) It controls body temperature and thirst
D) It produces red blood cells
Answer: C) It controls body temperature and thirst
15. The process that helps the body cool down by releasing sweat is called:
A) Vasodilation
B) Evaporation
C) Respiration
D) Osmosis
Answer: B) Evaporation
16. What effect does vasodilation have on body temperature?
A) It cools the body down
B) It increases body temperature
C) It maintains body temperature
D) It has no effect on body temperature
Answer: A) It cools the body down
17. What is the role of the liver in homeostasis?
A) Regulating body temperature
B) Storing glucose as glycogen
C) Excreting waste products
D) Transporting oxygen
Answer: B) Storing glucose as glycogen
18. Which of the following hormones is involved in regulating metabolism?
A) Insulin
B) Testosterone
C) Thyroxine
D) Estrogen
Answer: C) Thyroxine
19. Which of the following conditions is a result of the failure of homeostasis?
A) Diabetes
B) Healthy digestion
C) Proper oxygen transport
D) Body temperature regulation
Answer: A) Diabetes
20. What structure in the skin helps regulate body temperature by releasing sweat?
A) Sweat glands
B) Hair follicles
C) Sebaceous glands
D) Oil glands
Answer: A) Sweat glands
21. Which process maintains a stable internal environment by reversing deviations from the set point?
A) Positive feedback
B) Negative feedback
C) Feedback inhibition
D) Feedback enhancement
Answer: B) Negative feedback
22. Which hormone is secreted when blood calcium levels are too low?
A) Parathyroid hormone
B) Calcitonin
C) Insulin
D) Growth hormone
Answer: A) Parathyroid hormone
23. Which of the following is a method of thermoregulation in humans?
A) Shivering
B) Excretion of excess heat through urine
C) Increased salivation
D) Increased glucose production
Answer: A) Shivering
24. Which organ is primarily responsible for excreting excess nitrogenous waste from the body?
A) Lungs
B) Liver
C) Kidneys
D) Heart
Answer: C) Kidneys
25. In homeostasis, the hypothalamus functions as the:
A) Receptor
B) Control center
C) Effector
D) Stimulus
Answer: B) Control center
26. Which of the following is an example of positive feedback in the body?
A) Childbirth contractions
B) Body temperature regulation
C) Blood sugar regulation
D) Osmoregulation
Answer: A) Childbirth contractions
27. What happens during vasoconstriction to regulate body temperature?
A) Blood vessels dilate to release heat
B) Blood vessels constrict to conserve heat
C) Sweat production increases
D) The heart rate decreases
Answer: B) Blood vessels constrict to conserve heat
28. The term “homeostasis” was first introduced by:
A) Charles Darwin
B) Walter Cannon
C) Louis Pasteur
D) Gregor Mendel
Answer: B) Walter Cannon
29. Which of the following processes does NOT contribute to thermoregulation?
A) Sweating
B) Shivering
C) Excretion of toxins
D) Vasodilation
Answer: C) Excretion of toxins
30. Which of the following is a major function of the endocrine system in homeostasis?
A) To circulate blood throughout the body
B) To regulate the body’s metabolism and growth
C) To defend the body against infections
D) To help with digestion and absorption
Answer: B) To regulate the body’s metabolism and growth
These MCQs cover various aspects of homeostasis, including the roles of the brain, organs, hormones, and feedback mechanisms in maintaining a stable internal environment.