Endocrine Control (Review)

Question 1

Endocrine hormones

Answer 1

produced and released by endocrine glands, travel by blood to distant targets

Question 2

Neurocrine hormones

Answer 2

signal from neuron down its axon via blood to distant targets (includes neurotransmitters)

Question 3

Paracrine hormones

Answer 3

Signal from one cell type to neighbouring different cell types via diffusion (propagation of responses)

Question 4

Autocrine hormones

Answer 4

Signal to neighbouring identical cells or back to itself (self-regulation)

Question 5

Neurotransmitters

Answer 5

Neurocrine molecules secreted by neurons to a target cell w/rapid localised effect on specific cell; send fewer messages over smaller distances

Question 6

Neurohormones

Answer 6

Neurocrine molecules secreted by neurons into the blood to act on a distant target (eg hypothalamus to A and P pituitary, catecholamines from neurons in adrenal medulla)

Question 7

What are tropic hormones?

Answer 7

Hormones that control the secretion of another hormone

Question 8

What are trophic hormones?

Answer 8

Hormones that stimulate growth and development

Question 9

What are non-tropic hormones?

Answer 9

Exert effects directly on a target organ/cell

Question 10

Which hormones bind to cell surface receptors?

Answer 10

Peptides & Catecholamines (hydrophilic)

Question 11

How do plasma proteins regulate hormones?

Answer 11

Unbound form is active; tf serve as a reservoir to maintain equilibrium of unbound plasma hormones

Question 12

Negative feedback occurs by

Answer 12

long loops (classic); short loops; hormone feedback decreases production of that hormone

Question 13

Positive feedback control

Answer 13

Release of a hormone encourages further release

Question 14

Neuroendocrine feedback

Answer 14

via neuroendocrine reflexes - eg insulin stimulation by increased blood glucose and stretching of GI

Question 15

Diurnal and circadian rhythms are regulated by

Answer 15

the pineal gland (melatonin) and cortisol via the suprachiasmatic nucleus

Question 16

Down-regulation occurs by

Answer 16

endocytosis; target cell desensitization (requires more hormone for an effect)

Question 17

Antagonism allows for

Answer 17

fine tuning through the opposing responses of hormones eg insulin and glucagon

Question 18

Synergism operates by

Answer 18

multiple stimuli creating an effect that is mire than additive (eg glucagon, cortisol, adrenaline in blood glucose regulation)

Question 19

Permissive regulation

Answer 19

First hormone cannot exert effects without presence of a second hormone eg cortisol and adrenaline (won’t act on their own)

Question 20

What is a primary endocrine disorder?

Answer 20

Gland is abnormal - can’t produce hormone/overproduces hormone

Question 21

What is a secondary endocrine disorder?

Answer 21

Gland is normal but secretion rate and/or regulation are not working

Question 22

What decreases hormone activity?

Answer 22

hyposecretion (primary - gland abnormal; secondary - abnormal tropic hormone); increased removal from the blood; abnormal tissue response (lack of receptors or enzyme for cell response)

Question 23

What increases hormone activity?

Answer 23

hypersecretion (primary - gland abnormal; secondary - excessive stimulation); decreased plasma protein binding; decreased removal from blood (decreased activation and/or excretion)