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NEET 2019 · BiologyPrevious Year Question

Artificial light, extended work-time and reduced sleep-time disrupt the activity of

Answer: (B) Pineal gland. Answer: (b) Pineal gland Solution: The pineal gland secretes melatonin, which regulates the 24-hour (diurnal) rhythm of the body, including the normal rhythms of the sleep-wake cycle.

  1. A.Thymus gland
  2. B.Pineal gland✓
  3. C.Adrenal gland
  4. D.Posterior pituitary gland

Correct Answer

(B) Pineal gland

Solution & Explanation

Answer: (b) Pineal gland Solution: The pineal gland secretes melatonin, which regulates the 24-hour (diurnal) rhythm of the body, including the normal rhythms of the sleep-wake cycle. Artificial light, extended work-time and reduced sleep-time disturb this light-dependent melatonin secretion, thereby disrupting the activity of the pineal gland. NCERT Reference: Chapter 19, Page 242, Line(s) 21-25 — "Pineal secretes a hormone called melatonin. Melatonin plays a very important role in the regulation of a 24-hour (diurnal) rhythm of our body. For example, it helps in maintaining the normal rhythms of sleep-wake cycle, body temperature."

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