The endocrine system

Question 1

What is Autocrine secretion ?

Answer 1

A secretion the activates auto-receptors on the same cell or same type of neighbouring cell.

e.g. platelets using serotonin

Question 2

what is Paracrine secretion ?

Answer 2

A secretion that activates receptors on “follower” (post-synaptic) cell.

e.g Typical of “neurotransmission” at synapse to another nerve, muscle or gland cell.

Question 3

What is an endocrine secretion ?

Answer 3

This occurs from glands without ducts: secreted chemical travel in blood vessel

e.g. hormonal mediation, ACTH or insulin

Question 4

what is Exocrine secretion ?

Answer 4

Secretion that occurs from glands with ducts - not chemical communication: Fluid secretions that pass out of the body

e.g. pancreatic digestive juice into the gut lumen

Question 4

what is Exocrine secretion ?

Answer 4

Secretion that occurs from glands with ducts - not chemical communication: Fluid secretions that pass out of the body

e.g. pancreatic digestive juice into the gut lumen

Question 5

what is the regulatory organ in the endocrine system ?

Answer 5

The Neuroendocrine Hypothalamus

Question 6

what are the major endocrine glands ?

Answer 6

1 Pineal gland
2 Pituitary gland
3 Thyroid gland
4 Thymus
5 Adrenal gland
6 Pancreas

Question 7

what is a self limiting response ?

Answer 7

• tending to attenuate perturbations
• Promotes dynamic equilibrium (balance) at a set point

Question 8

what is the endocrine control organised into ?

Answer 8

Axes

Question 9

What does the hypothalamus do ?

Answer 9

• produces releasing (inhibitory) factors acting on the pituitary.
• pituitary secretes into the circulation trophic or stimulating hormones.

Question 10

what are the 3 HP end organ axes that exhibit feedback inhibition ?

Answer 10

1. HP-Adrenal - via GCS - is catabolic, anti-inflammatory/immunosuppressive.
2. HP-Thyroid - via TH - acts on basal metabolic rate (BMR).
3. HP-Gonadal - via pituitary FSH and LH - acts on the ovaries or testis - to control reproductive maturity / phases.

Question 11

what is hypertrophy ?

Answer 11

growth/downstream in the chain of linked organs.

Question 12

what is hypotrophy ?

Answer 12

atrophy/shrinkage/ “upstream”
in the chain of linked organs.

Question 13

what are the 2 possible consequences of negative feedback ?

Answer 13

Trophic or Atrophic

Question 14

what is a trophic response ?

Answer 14

consequences of feed-forward activation

Question 15

what is atrophic response ?

Answer 15

consequences of feedback inhibition

Question 15

what is atrophic response ?

Answer 15

consequences of feedback inhibition

Question 16

what are the 2 types of receptor transduction ?

Answer 16

• Response to transmitters tends to be fast/reversible, involves conformational change
• Response to hormones is delayed, persistent or permanent, may involve gene transcription

Question 16

what are the 2 types of receptor transduction ?

Answer 16

• Response to transmitters tends to be fast/reversible, involves conformational change
• Response to hormones is delayed, persistent or permanent, may involve gene transcription