NEET 2011 · Class 11

Chemical Coordination and Integration

The 24 hour (diurnal) rhythm of our body such as the sleep-wake cycle is regulated by the hormone

  1. (A)calcitonin
  2. (B)prolactin
  3. (C)adrenaline
  4. (D)melatonin

The NCERT line that answers it

Verbatim line

Melatonin plays a very important role in the regulation of a 24-hour (diurnal) rhythm of our body.

Chapter
Chemical Coordination and Integration
Section
19.2.3 The Pineal Gland
Page
3
Words matched
31 of 31

The answer appears as a continuous sentence in NCERT. This is that sentence.

How this line gives the answer

0, emb=1.0, combined=1.0). Verified: high — The span explicitly states that melatonin regulates the 24-hour (diurnal) rhythm of our body, which directly matches the MCQ's question about the hormone regulating the sleep-wake cycle.

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