The hormone that stimulates milk ejection during breastfeeding is:
A. Prolactin
B. Estrogen
C. Progesterone
D. Oxytocin
Answer: Option D
Solution (By JKExamLibrary)
Oxytocin, released from the posterior pituitary in response to suckling, causes contraction of myoepithelial cells around mammary alveoli, forcing milk into ducts (let-down reflex). Prolactin stimulates milk synthesis. Estrogen and progesterone inhibit milk secretion during pregnancy.
Explanation:
Hemolysis is the rupture or destruction of red blood cells, releasing hemoglobin. Hemopoiesis is blood cell formation, hemostasis is stopping bleeding, erythropoiesis RBC production.
Assertion (A): The bacterial cell wall is composed of peptidoglycan.
Reason (R): Peptidoglycan provides structural strength and prevents osmotic lysis.
A.A false, R true.
B.A true, R false.
C.Both A and R are true, but R is not the correct explanation.
D.Both A and R are true, and R is the correct explanation.
Explanation:
Bacterial cell walls contain peptidoglycan (murein), a unique polymer that maintains cell shape and protects against osmotic pressure. The reason correctly explains why peptidoglycan is essential.
Explanation:
Vitamin C is a cofactor for the enzyme tyrosinase, which is involved in melanin synthesis. Vitamin A is for vision, B₆ for amino acid metabolism, D for calcium.
No comments yet. Be the first to start the discussion!