endocrine pt 1

Question 1

example of autocrine communication substance

Answer 1

prostaglandins

Question 2

example of paracrine communication substance

Answer 2

somatostatin on insulin secretion

Question 3

what does autocrine mean

Answer 3

cell secretes substance into interstitial fluid, substance then effects that same cell

Question 4

what does paracrine mean

Answer 4

substance is released into interstitial fluid and then effects neighbouring cell

Question 5

where are hormones secreted from in neuroendocrine messages

Answer 5

nerve cells

Question 6

where do neurones store hormones

Answer 6

in granules in the axon terminal

Question 7

2 examples of hormones secreted by neurones

Answer 7

oxytocin and arginine vasopressin

Question 8

what is another name for arginine vasopressin

Answer 8

ADH - antidiuretic hormone

Question 9

4 different types of endocrine hormones

Answer 9

peptide, steroid, hormones derived from tyrosine and eicosanoids (prostaglandins)

Question 10

peptide hormones

Answer 10

strings of amino acids, includes those from hypothalamus, anterior and posterior pituitary glands, pancreas and GIT

Question 11

steroid hormones

Answer 11

derived from cholesterol, includes cortisol, aldosterone and sex hormones

Question 12

hormones derived from tyrosine

Answer 12

thyroid hormones and catecholamines

Question 13

where are the catecholamines secreted from

Answer 13

adrenal medulla

Question 14

examples of catecholamines

Answer 14

adrenaline and noradrenaline

Question 15

where are cortisol and aldosterone produced

Answer 15

adrenal cortex

Question 16

what effect does the chemical make up of a hormone have on it

Answer 16

effects the way they are synthesised, stored, transported and how they act

Question 17

peptide hormone synthesis

Answer 17

they are secreted out the cell, synthesised in same way that proteins are when they are exported

Question 18

steps of peptide hormone synthesis

Answer 18

1. transcription of gene into mRNA
2. translation in ribosome (RER)
3. pre signal is cleaved
4. now a prohormone -> goes to the golgi complex
5. hormone is packaged into secretory granules
6. exocytosis

Question 19

what is preprohormone

Answer 19

first molecule made in peptide hormone synthesis, has a “pre” segment which is a hydrophobic signal peptide. Tells the cell there needs to be more processing and packaging

Question 20

Steroid hormone synthesis

Answer 20

cholesterol converted by enzymatic conversions into a hormone

Question 21

steroid hormone transportation

Answer 21

must be bound to plasma carrier proteins to travel in aqueous blood plasma as they are lipophilic

Question 22

peptide vs steroid and thyroid: solubility

Answer 22

peptide are hydrophilic and the others are lipophilic

Question 23

peptide vs steroid and thyroid: binding to plasma proteins

Answer 23

peptide are free hormones so don’t bind but thyroid and steroid do with weak, reversible bonds

Question 24

peptide vs steroid and thyroid: half life

Answer 24

peptides have a half life of minutes whereas the others have hours steroid /days thyroid

Question 25

what does binding to plasma proteins do, other than transport, for hormones

Answer 25

delays metabolism, provides circulating reservoir of hormones, biologically inactive

Question 26

peptide hormone action

Answer 26

interact w plasma membrane receptors

Question 27

2 types of plasma membrane receptors that peptide hormones interact w

Answer 27

G protein receptors, tyrosine kinase linked receptor

Question 28

what physiological response is a result of the signal transduction triggered by peptide hormones

Answer 28

altered enzyme activities, ion channel activity change, altered expression of specific proteins

Question 29

steroid and thyroid hormone action

Answer 29

interact with intracellular receptors which are regarded as hormone-regulated transcription factors

Question 30

examples of receptors that steroid and thyroid hormones interact with

Answer 30

cytosolic and nuclear receptors

Question 31

what happens when the steroid hormone/ thyroid hormone binds to the receptor

Answer 31

the complex then goes and binds to the promotor of specific genes and effect gene expression

Question 32

what is the endocrine axis

Answer 32

interactions between the hypothalamus, pituitary and peripheral endocrine glands which show feedback regulation

Question 33

what effects what in the endocrine axis (general model)

Answer 33

hypothalamus releases releasing hormone which stimulates or inhibits the anterior pituitary which releases tropic hormone which stimulates peripheral endocrine gland which releases peripheral hormone which leads to a target cell response

Question 34

what happens if the peripheral hormone level is too high

Answer 34

activation of the negative feedback loops which decrease effects of the hypothalamus and the anterior pituitary

Question 35

what does the short feedback loop from the tropic hormone effect

Answer 35

hypothalamus

Question 36

what does some feedback from the target cell effect

Answer 36

hypothalamus

Question 37

what are neuroendocrine reflexes

Answer 37

when there is input from higher centres in the brain e.g. stress increasing hypothalamus activity which leads to cortisol release

Question 38

what is the diurnal rhythm

Answer 38

day-night hormone levels

Question 39

what is the circadian rhythm

Answer 39

cycle of hormone levels in a day

Question 40

what does hypersecretion mean

Answer 40

hormone excess

Question 41

what does hyposecretion mean

Answer 41

lack of hormone

Question 42

why would someone have decreased target-cell responsiveness

Answer 42

due to differing receptor levels and downstream enzyme levels

Question 43

what is a primary endocrine disorder cause

Answer 43

when it is associated with gland that makes the hormone

Question 44

what is a secondary endocrine disorder cause

Answer 44

due to another condition or abnormal hypothalamic -pituitary secretion of tropic hormone

Question 45

what is cushings syndrome

Answer 45

excess cortisol

Question 46

treatment for hormone deficiency

Answer 46

hormone replacement

Question 47

treatment for hormone excess

Answer 47

block production w drugs

Question 48

treatment for decreased cell responsiveness

Answer 48

drugs to enhance cellular response

Question 49

treatment for tumour effecting hormone levels

Answer 49

radiotherapy or surgery