Question:
Melatonin is secreted by:
Melatonin is secreted by:
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The pineal gland is the primary source of melatonin, a hormone crucial for regulating the circadian rhythm. Its secretion increases in response to darkness.
Updated On: Feb 24, 2026
- Thyrotrophs
- Gonadotrophs
- Pineal gland
- Adrenal gland
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The Correct Option is C
Solution and Explanation
Step 1: Understanding melatonin secretion. Melatonin is a hormone primarily secreted by the pineal gland, a small endocrine gland located in the brain.
Step 2: Role of melatonin. Melatonin regulates the sleep-wake cycle (circadian rhythm) and is influenced by the light-dark cycle. Its secretion increases in darkness and decreases in light.
Step 3: Why other options are incorrect.
- (A) Thyrotrophs: These are cells in the anterior pituitary gland that secrete thyroid-stimulating hormone (TSH), not melatonin.
- (B) Gonadotrophs: These are pituitary cells that secrete gonadotropins like LH and FSH.
- (D) Adrenal gland: Secretes hormones like cortisol, aldosterone, and adrenaline, but not melatonin.
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