Correct option is A
Explanation-
The pituitary gland has two main parts:
1. Anterior Pituitary (Adenohypophysis): Produces and secretes many hormones (GH, prolactin, ACTH, TSH, LH, FSH).
2. Posterior Pituitary (Neurohypophysis): Releases hormones synthesized in the hypothalamus (oxytocin and vasopressin).
There is also a vestigial intermediate lobe, more prominent in some animals, but rudimentary in adult humans.
Statement A- Oxytocin and vasopressin are synthesized in posterior pituitary
Incorrect
These hormones are released from the posterior pituitary. BUT they are synthesized in the hypothalamus (specifically: supraoptic and paraventricular nuclei). The posterior pituitary acts as a storage and release site, not the site of synthesis.
Statement B- Prolactin is synthesized from anterior pituitary
Correct
Prolactin is secreted by lactotroph cells in the anterior pituitary. It plays a role in milk production and is regulated by dopamine (inhibitory).
Statement C - α and β MSH are secreted from intermediate lobe of pituitary in adult humans
Incorrect
The intermediate lobe is poorly developed in adult humans. While α-MSH is derived from POMC, it is mainly produced in the skin (keratinocytes) and hypothalamus in adults. Therefore, in humans, intermediate lobe plays little to no role in α-MSH and β-MSH secretion.
Statement D- Growth hormone secretion from anterior pituitary is stimulated by hyperglycemia
Incorrect
GH secretion is actually stimulated by hypoglycemia, exercise, stress, and sleep. Hyperglycemia inhibits GH secretion. This statement is physiologically inaccurate.
Statement E- Prolactin secretion is markedly increased by sleep
Correct
Prolactin levels increase significantly during sleep, particularly during REM and early morning stages. This helps regulate circadian rhythms and may contribute to lactation behavior.
Incorrect statements - A, C and D
Correct option is a - A , C and D
