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NEET 2021 · BiologyPrevious Year Question

Which of these is not an important component of initiation of parturition in humans? (NEET 2021)

Answer: (B) Release of Prolactin. Answer: (B) Release of Prolactin Solution: Parturition is induced by a neuroendocrine mechanism in which the foetal-ejection-reflex signals trigger oxytocin release, oxytocin causes strong uterine contractions, and prostaglandins together with a rising estrogen/progesterone ratio support the process.

  1. A.Release of Oxytocin
  2. B.Release of Prolactin✓
  3. C.Increase in estrogen and progesterone ratio
  4. D.Synthesis of prostaglandins

Correct Answer

(B) Release of Prolactin

Solution & Explanation

Answer: (B) Release of Prolactin Solution: Parturition is induced by a neuroendocrine mechanism in which the foetal-ejection-reflex signals trigger oxytocin release, oxytocin causes strong uterine contractions, and prostaglandins together with a rising estrogen/progesterone ratio support the process. Prolactin governs milk synthesis (lactation), not the initiation of labour, so it is NOT a component of initiation of parturition. NCERT Reference: Ch 2, p.38, line 30 — "triggers release of oxytocin from the maternal pituitary. Oxytocin acts on"

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