Endocrine 1: Hormonal Signals

Question 1

the endocrine system is a complex network consisting of ___, ___ and___

Answer 1

glands; hormones; effect on target

Question 2

t/f glands secrete specific things based on specific stimulus

Answer 2

t

Question 3

do endocrine glands have ducts?

Answer 3

no

Question 4

endocrine glands empty directly into ___

Answer 4

blood

Question 5

what are hormones? where are they produced and secreted?

Answer 5

a variety of chemical signalling molecules produced by the endocrine cells or glands and secreted into the blood

Question 6

t/f hormones can travel in the bloodstream to target cells that are both nearby or far away

Answer 6

t

Question 7

hormones act on specific receptors either on the ___ or __

Answer 7

cell membrane or inside the cell

Question 8

what is the major signalling pathway in the endocrine system?

Answer 8

classical endocrine signalling

Question 9

what are the 4 types of signalling in the endocrine system?

Answer 9

1. classical endocrine
2. neuroendocrine
3. autocrine regulation
4. paracrine regulation

Question 10

what happens in classic endocrine signalling?

Answer 10

hormone leaves endocrine cell and travels through the blood to a target cell anywhere in the body

Question 11

what happens in neuroendocrine signalling?

Answer 11

neurohormones are secreted from neuroendocrine cells and travel through the blood to a target cell anywhere in the body

Question 12

what happens in autocrine regulation?

Answer 12

the hormone that is released acts on the same cell that released it

Question 13

what happens in paracrine regulation?

Answer 13

released hormone acts on a nearby cell

Question 14

the main function of many hormones is to stimulate the release of ____

Answer 14

other hormones

Question 15

what are the 2 ways hormones maintain homeostasis?

Answer 15

metabolism and osmoregulation

Question 16

what are the 6 main functions of hormones?

Answer 16

1. stimulate other hormones
2. homeostasis
3. coordinate develpoment
4. regulate groth and morphology
5. reproduction
6. behavioural and social interaction

Question 17

t/f adipocytes have important endocrine functions

Answer 17

t

Question 18

which glands only have endocrine function?

Answer 18

pituitary and thyroid

Question 19

which glands have endocrine and exocrine functions?

Answer 19

pancreas

Question 20

which part of pancreas secretion is Eno/exo ?

Answer 20

endocrine : insulin

exocrine: digestive function

Question 21

what are the 3 major types of stimuli in the endocrine system?

Answer 21

1. humoral
2. neural
3. hormonal

Question 22

what is humeral stimulus?

Answer 22

control of hormone release based on changes in extracellular fluids (eg Ions, glucose levels)

Question 23

explain how the parathyroid glands are involved in humeral stimulus when blood Ca is low

Answer 23

parathyroid senses low Ca and secreted PTH which acts to raise Ca

Question 24

what is neural stimulus?

Answer 24

when the nervous system directly stimulates the endocrine glands to release hormones (adrenaline and noradrenaline in response to stress)

Question 25

how does the neural stimulation of the endocrine system work?

Answer 25

the preganglion sympathetic fibers from the spinal cord stimulated the adrenal medulla cells causing the adrenal gland to release catecholamines into the bloodstream

Question 26

what is hormonal stimulation?

Answer 26

release of hormone in response to another hormones

Question 27

the hypothalamus secreted hormones that stimulates hormone release from the ___, which stimulates hormone release from ___

Answer 27

anterior pituitary; other endocrine glands (such as gonads, thyroid, adrenal cortex)

Question 28

amino acid derivative hormones are derived form ___

Answer 28

tyrosine

Question 29

amino acid derivative hormones are released from the ___ and __

Answer 29

thyroid and adrenal medula

Question 30

what are 2 examples of amino acid derivative hormones?

Answer 30

epinephrine and T4/T3

Question 31

peptide and protein hormones are made of

Answer 31

peptides

Question 32

peptide hormone are secreted from the __ and __ _

Answer 32

anterior pituitary and pancreas

Question 33

what are 2 examples of peptide hormones?

Answer 33

gastrin and insulin

Question 34

peptide hormones mostly bind to what type of receptor?

Answer 34

cell surface

Question 35

steroid hormones are derived from ___

Answer 35

cholesterol

Question 36

steroid hormones are secreted from the __ and __

Answer 36

adrenal cortex and gonads

Question 37

2 examples of steroid hormones

Answer 37

testosterone and oestrogen

Question 38

what are tropic hormones?

Answer 38

hormones secreted to act on endocrine cells which will then secrete their own (non-tropic) hormones

Question 39

what are tropic hormones?

Answer 39

secreted by the endocrine cells and then act directly on effector

Question 40

what is the function tropic hormones/

Answer 40

regulate production and secretion of hormones by other endcrine cells

Question 41

2 examples of tropic hormones

Answer 41

FSH and TSH

Question 42

what is the function of non-tropic hormones?

Answer 42

regulate cellular functions ranging from autophagy and metabolism atoms proliferation and cell death

Question 43

give 2 examples of non-tropic hormones

Answer 43

oestrogen and vasopressin (ADH)

Question 44

wate soluble hormones bind to ___ receptor and activate ___(quickly or slowly) and have _____term effects

Answer 44

cell surface; quickly; long

Question 45

MOA of water soluble hormones

Answer 45

bind to cell surface receptor, second messengers activate or deactivate enzyme that produce cellular response

Question 46

lipophilic hormones bind to ___ receptors and act ____ and have ____term effects

Answer 46

cytoplasmic and nucleic; slowly; long

Question 47

MOA for lipophilic hormones (action in nuclear)

Answer 47

1. cross membrane 2. bind to cytosolic receptor (kept inactive by heat shock proteins) 3. HSP released, conformation change of receptor 4. receptor and hormone enter the nuclei 5. bind to DNA and initiate transcription 6. mRNA enters cytoplasm and new protein is made

Question 48

what is the most common receptor type in the endocrine system?

Answer 48

GPCR

Question 49

how does hormonal signalling by GPCRs work?

Answer 49

binding activates G protein (GI) which activates adenyl cyclase to make cAMP which activates PKA to phosphorylate proteins (enzymes) to carry out response

Question 50

what happens when an activated G protein activates PLC?

Answer 50

turns PIP2 into IP3 and DAG, IP3 opens Ca channels which acts as a second messenger to activate various proteins with different responses

Question 51

___% of all drugs are GPCR targeting

Answer 51

50

Question 52

2 examples og GPRC targeting drugs

Answer 52

sumatriptan (migraine) and oxytocin (induce labor)

Question 53

thyroid hormones act very much like steroid hormones except that their receptor are generally always ___

Answer 53

already in the nucleus

Question 54

thyroid hormones most likely cross the cell membrane by ___ but there may also be ___ involves

Answer 54

difusion; carrier mediated transport

Question 55

cell surface receptors can be ___ and __ in response to prolonged hormone release / levels

Answer 55

internalized and degraded

Question 56

most endocrine feedback loops are __, meaning ___

Answer 56

negative; meaning when target tissues make more of the desired product, the endocrine uncharge of making the hormone to stimulate the production slows down on hormone release

Question 57

an increase in plasma glucose causes release of what hormone?

Answer 57

insulin