Question

Median eminence is part of
(a)Anterior pituitary
(b)Thalamus
(c)Neurohypophysis
(d)None of the above

Answer 1

Hint: Median eminence is part of the structure which is responsible for secreting the hormones oxytocin and vasopressin. These two hormones are actually produced by the hypothalamus and sent to this structure axonally and then this structure releases them into the blood.

Complete answer:
 The median eminence is part of the neurohypophysis. Neurohypophysis (pars nervosa) is also known as the posterior pituitary and consists of the posterior lobe, median eminence, and infundibular stalk. Median eminence is the place where the neuroendocrine cells of the hypothalamus project their axons at the base of the brain. The releasing and inhibiting hormones that are released by these neuroendocrine cells pass through this median eminence and then go to the anterior pituitary to control it.

Additional Information: Let us look at the structure of the pituitary gland in detail. The pituitary gland consists of the anterior lobe and posterior lobe along with an intermediate lobe.
Anterior pituitary: Also known as adenohypophysis and consists of pars distalis and pars intermedia. The pars distalis region is responsible for the production of the growth hormone (GH). prolactin (PRL), thyroid-stimulating hormone (TSH), adrenocorticotropic hormone (ACTH), luteinizing hormone (LH), and follicle-stimulating hormone (FSH).
Pars intermedia secretes the hormone melanocyte-stimulating hormone (MSH).
Posterior pituitary: It is present on the posterior side of the pituitary gland as the name suggests and secretes two hormones that are produced in the hypothalamus known as oxytocin and vasopressin.
So, the correct option is ‘Neurohypophysis’.

Note: -The hormone oxytocin is responsible for the contraction of smooth muscles which help during childbirth and milk ejection from the mammary glands.
-The hormone vasopressin acts on the later parts of the tubules of a nephron and causes reabsorption of water and electrolytes.
-Since, vasopressin stops the production of urine (diuresis) it is known as an anti-diuretic hormone.
-Deficiency of vasopressin leads to Diabetes insipidus.