Question

Oxytocin is secreted by

• A. Hypothalamus
• B. Anterior lobe of pituitary
• C. Middle lobe of pituitary
• D. Posterior lobe of pituitary

Answer 1

The correct option is D

Posterior lobe of pituitary

The correct option is D:

Explanation of the correct option:

1. Oxytocin is secreted by paraventricular nuclei cells of the hypothalamus and transported through axons to the posterior lobe of the pituitary.
2. Neurohypophysis (posterior pituitary) is a storage -releaser center for the hormone synthesis by the hypothalamus.
3. Oxytocin acts on the smooth muscles of the body and stimulates their concentration i.e. during childbirth oxytocin causes contraction of uterine muscles.
4. Oxytocin also helps in milk ejection from the ducts in the breast to the nipples.

Explanation of the incorrect option:

Option A:

Hypothalamus is the master of the master gland that sends the information through releasing hormones to the pituitary which in turn secretes hormones that directly or indirectly control the activities of other endocrine glands.

Option B:

Anterior pituitary gland (adenohypophysis) gives rise to TSH, ACTH,FSH,LH,PRL,GH.

Option C:

The middle lobe of the pituitary also called the intermediate pituitary secretes melanocyte-stimulating hormone(MSH).

Final answer: Oxytocin is secreted by the posterior lobe of the pituitary.