Hypothalamus & Pituitary

Question 1

……lobe is rudimentery in humans it secretes…..

Answer 1

Intermediate
MSH

Question 2

The storage granules in neurohypophysis contain…….

Answer 2

Free vasopressin or oxytocin with corresponding neurophysin

Question 3

Neurohormones of hypothalamus that act on adenohypophysis act through…….

Answer 3

All act through inc cAMP

Question 4

Define each of the following:
1. Long feedback loop
2. Short feedback loop
3. Ultra-short feedback loop

Answer 4

1. Target organ hormone inhibits affects the hypothalamus/pituitary to inhibit it appropriate releasing hormone and tropic factor
2. Hormone secreted from anterior pituitary inhibits secretion of appropriate releasing hormone from hypothalamus
3. Hormone secreted from hypothalamus affects the hypothalamus (inhibits its ownse secretion & synthesis)

Question 5

Mention an example of +ve feedback mechanism in hormonal regulation

Answer 5

The surge of lutenizing hormone that occurs in response to stimulatory effect of estrogen on the anterior pituitary before ovulation. The secreted LH then acts on the ovaries to stimulate additional secretion of estrogen, which increases LH.