NEET 2025 MCQ with Answer Explanation : Chemical coordination and Integration.

Question 41:
What role does cortisol play in the body?

A) Increases insulin sensitivity
B) Regulates sodium levels
C) Increases blood sugar during stress
D) Promotes growth

Answer: C) Increases blood sugar during stress

Explanation: Cortisol is released during stress and increases blood sugar levels by promoting gluconeogenesis in the liver.

Question 42:
Which of the following is NOT a function of insulin?

A) Promotes glucose uptake by cells
B) Stimulates glycogen synthesis
C) Increases blood sugar levels
D) Inhibits fat breakdown

Answer: C) Increases blood sugar levels

Explanation: Insulin decreases blood sugar levels by promoting glucose uptake and storage; it does not increase blood sugar.

Question 43:
Which hormone acts to lower blood calcium levels?

A) Calcitonin
B) Parathyroid hormone (PTH)
C) Aldosterone
D) Testosterone

Answer: A) Calcitonin

Explanation: Calcitonin lowers blood calcium levels by inhibiting osteoclast activity in bones and promoting calcium excretion in the kidneys.

Question 44:
What is the role of the hormone insulin-like growth factor (IGF)?

A) Increases blood glucose
B) Promotes growth and development
C) Regulates calcium levels
D) Inhibits appetite

Answer: B) Promotes growth and development

Explanation: Insulin-like growth factor (IGF) promotes growth and development in tissues, especially during childhood and adolescence.

Question 45:
Which of the following hormones is involved in the body’s circadian rhythms?

A) Cortisol
B) Insulin
C) Melatonin
D) Thyroxine

Answer: C) Melatonin

Explanation: Melatonin plays a key role in regulating circadian rhythms, signaling to the body when it is time to sleep.

Question 46:
Which hormone stimulates the adrenal cortex to produce glucocorticoids?

A) Follicle-stimulating hormone (FSH)
B) Luteinizing hormone (LH)
C) Adrenocorticotropic hormone (ACTH)
D) Thyroid-stimulating hormone (TSH)

Answer: C) Adrenocorticotropic hormone (ACTH)

Explanation: ACTH stimulates the adrenal cortex to produce glucocorticoids, including cortisol.

Question 47:
Which hormone increases the reabsorption of sodium in the kidneys?

A) Glucagon
B) Aldosterone
C) Insulin
D) Estrogen

Answer: B) Aldosterone

Explanation: Aldosterone promotes sodium reabsorption in the kidneys, which helps regulate blood pressure and volume.

Question 48:
What is the primary function of the hormone leptin?

A) Increases appetite
B) Regulates energy balance
C) Stimulates growth
D) Increases blood pressure

Answer: B) Regulates energy balance

Explanation: Leptin is involved in regulating energy balance and inhibiting hunger, thereby playing a role in body weight regulation.

Question 49:
Which of the following hormones is produced by the pancreas?

A) Thyroxine
B) Insulin
C) Cortisol
D) Adrenaline

Answer: B) Insulin

Explanation: Insulin is produced by the pancreas and plays a crucial role in regulating blood glucose levels.

Question 50:
Which hormone is secreted by the ovaries?

A) Testosterone
B) Estrogen
C) Insulin
D) Cortisol

Answer: B) Estrogen

Explanation: Estrogen is produced by the ovaries and is involved in regulating the menstrual cycle and female reproductive functions.