Oxytocin and Milk Ejection — NEET Biology
✅ Asked in NEET 2023Hormone responsible for the milk ejection reflex is: (NEET 2023)
Hormone responsible for the milk ejection reflex is: (NEET 2023)
Which one of the following hormone pairs is not antagonistic (opposing) in action? (NEET 2022)
Which hormone regulates reabsorption of water in kidney tubules? (NEET 2021)
Answer & NCERT explanation
Correct answer: B — Oxytocin
Oxytocin is responsible for milk ejection reflex during breastfeeding. When baby sucks, neural signals trigger oxytocin release from posterior pituitary, causing smooth muscle contraction around mammary alveoli. Prolactin stimulates milk production, while estrogen and progesterone prepare mammary glands. NCERT clearly mentions oxytocin's role in lactation.
Read more NCERT concept on the PYQ
MSH acts on the melanocytes (melanin containing cells) and regulates pigmentation of the skin. Oxytocin acts on the smooth muscles of our body and stimulates their contraction. In females, it stimulates a vigorous contraction of uterus at the time of child birth, and milk ejection from the mammary gland. Vasopressin acts mainly at the kidney and stimulates resorption of water and electrolytes by the distal tubules and thereby reduces loss of water through urine (diuresis). Hence, it is also called as anti-diuretic hormone (ADH).
NTA repeatedly tests oxytocin's dual role: stimulating uterine contractions during labor AND milk ejection from mammary glands in females. Students often confuse oxytocin with prolactin—prolactin produces milk, but oxytocin ejects it. Another trap: thinking oxytocin only works during childbirth, ignoring its role in lactation. The key distinction is that oxytocin acts on smooth muscles to cause contraction, while prolactin acts on mammary tissue to produce milk. For NEET: remember oxytocin = contraction/ejection; prolactin = production. This hormone pair appears frequently because it tests understanding of multiple endocrine functions in female reproduction.
What does NCERT say about MSH acts on melanocytes?
Has this concept appeared in NEET?
Which chapter is this from?
Through deep analysis of NEET and NTA, 88 of 90 questions from the NEET 2026 paper were matched straight from the MedicNEET Biology question bank.
88/90MedicNEET's Biology question bank is built from the same NCERT lines NTA picks repeatedly. Not random MCQs — questions crafted exactly like NTA crafts them.