Endocrine Physiology Part 2

Question 1

Name and explain three ways in which hormones interact

Answer 1

Synergism- the effect of two hormones is more than the effect of each hormone (1+1=3).
Permissiveness- One hormone cannot fully function without the presence of the other.
Antagonism- Two hormones oppose each other.

Question 2

The stalk that connects the pituitary gland to the brain.

Answer 2

Infundibulum

Question 3

Structure that links and co-ordinates the nervous and endocrine system

Answer 3

Hypothalamus

Question 4

Hormones produced in the hypothalamus are referred to as:

Answer 4

Neurohormones

Question 5

How is the hypothalamus linked to the adenohypophysis, and the neurohypophysis(2)

Answer 5

Adenohypophysis via the hypothalamo-hypophysial portal system.
Neurophysis via the hypothalamo-neurohypophysial tract

Question 6

Term used for stimulating hormones

Answer 6

Librins

Question 7

Term used for inhibiting hormones

Answer 7

Statins

Question 8

Release of librins/statins controlled by: (2)

Answer 8

Negative feedback of target hormones and circulating nutrients
External factors

Question 9

What are the functions of oxytocin and vasopressin

Answer 9

Oxytocin- stimulate milk ejection and parturition.
Vasopressin/ antidiuretic hormone- maintain water balance in the body.

Question 10

From which part of the hypothalamus are ADH and Oxytocin produced?(2)

Answer 10

ADH- from the supraoptic nucleus
Oxytocin-from the paraventricular nucleus

Question 11

Functions of vasopressin(2)

Answer 11

-Increases H2O reabsorption
- Causes vasoconstriction at high concentrations.

Question 12

Two food intake that inhibits ADH secretion

Answer 12

-alcohol and caffeine

Question 13

Two mechanisms that regulate the secretion of ADH

Answer 13

Osmoreceptors
Baroreceptors

Question 14

What is the diff between osmoreceptors and baroreceptors

Answer 14

Osmoreceptors detect changes in osmotic pressure.
Baroreceptors detect changes in blood pressure.

Question 15

Diseases caused by the malfunction of ADH(briefly explain)

Answer 15

Central diabetes insipidus- pituitary gland is unable to secrete ADH.
Nephrogenic diabetes insipidus- collecting ducts are unable to respond to the secreted ADH due to a mutation in the V2 receptor.
Syndrome of inappropriate ADH secretion- can be caused by drugs, tumors or injury, causes continous secretion of ADH or increased action of ADH on collecting ducts.

Question 16

Defect of GH deficiency

Answer 16

Short stature in children

Question 17

What does excess GH cause

Answer 17

Gigantism in children, acromegaly in adults

Question 18

Factors that causes the release or inhibition of TSH

Answer 18

• Plasma concentration of thyroxine.
  -Thyrolibrin (TRH)

Question 19

Factors that causes the release or inhibition of ACTH

Answer 19

Corticolibrin
Negative feedback by cortisol

Question 20

Factors that causes the release or inhibition of Gonadotropins

Answer 20

Concentration of sex hormones as negative feedback
Lulibrin
Follitropin

Question 21

What is the inhibitor of prolactin?

Answer 21

Dopamine

Question 22

What is the inhibitor if GH?

Answer 22

Somatostatin