sem 1 : Hormone synthesis and action

Question 1

can protein hormones transverse the membrane

Answer 1

no

Question 2

what do protein hormones come from

Answer 2

large precursor molecules called pre hormones

Question 3

what do steroid hormones come from

Answer 3

low molecule weight precursors

Question 4

are steroid hormones lipid soluable

Answer 4

yes

Question 5

how to form secretory granules

Answer 5

1. N terminal binds to SRP
2. SRP binds to SRP receptors on RER
3. passes through into lumen
4. removed by peptidases

Question 6

once the pre-prohormone is cleaved, what remains?

Answer 6

just the hormone without the signal sequence

Question 7

what is a pre-pro hormone

Answer 7

signal sequence and hormone

Question 8

where is cholestrol made

Answer 8

liver

Question 9

1. where is cholestrol stored in

Answer 9

steroid synthesising cells

Question 10

2. what hormone stimulates a cascade to occur

Answer 10

trophic hormone

Question 11

2. what is the cascade include

Answer 11

protein kinase A

Question 12

3. what protein is activated after the cascade

Answer 12

StAR

Question 13

4. where does StAR protein transport the cholestrol

Answer 13

inner membrane on mitochondria

Question 14

5. what do they enzymes inside the mitochondria do to the cholestrol

Answer 14

cleave it to form the STEROID

Question 15

what can cholesterol be turned into

Answer 15

pregnenolone

Question 16

what is pregnenolone

Answer 16

precursor for many steroid molecules

Question 17

pregnenolone can be turned into 2 things

Answer 17

progesterone

17alphaOH progesterone

Question 18

17alphaOH progesterone can be turned into 2 things

Answer 18

cortisol

androgens

Question 19

what is oestrogens derived from

Answer 19

androgens

Question 20

what is aldosterone derived from

Answer 20

progesterone

Question 21

what will a deficiency in aromatase lead to

Answer 21

androgens cant be converted into oestrogens

Question 22

what will aromatase deficiency look like in

1. males
2. females
3. boys

Answer 22

1. no epiphyseal closure
2. male like characteristics
3. early puberty

Question 23

with thyroid hormone synthesis which enzyme oxidises iodide to iodine

Answer 23

thyroid peroxidase(TPO)

Question 24

what is the thyroglobulin droplets in the follicle cell eventually released as

Answer 24

T3 and `T4, stimulated by TSH

Question 25

what is a goitre

Answer 25

enlargement of thyroid gland

Question 26

what is graves disease

Answer 26

antibodies acting on thyroid gland to stimulate excess thryoid hormones- eye disease

Question 27

how to protein hormones work

Answer 27

bind to cell surface receptors to activate secondary messangers

Question 28

how do steroid hormones work

Answer 28

binding to intracellular receptors

Question 29

what are all steroid receptors

Answer 29

transcription factors

Question 30

what is a transcription factor

Answer 30

binds to DNA to initiate transcription

Question 31

what two types of receptors are found for protein hormones

Answer 31

g protein coupled | tyrosine kinase

Question 32

what could a defective g protein coupled receptor lead to

Answer 32

hypergonadotrophic hypogonadism- inactivating mutation of LH receptor

Question 33

what could a defective g protein lead to

Answer 33

Psuedohypoparathyroidism due to PTH receptor inactivation

Question 34

what are the domains of a steroid hormone receptor

Answer 34

A-F

Question 35

which domain on the steroid hormone receptor(transcription factor) is the DNA binding region

Answer 35

C

Question 36

what else is on the C-domain which allows the DNA to be locked in

Answer 36

2 zinc fingers

Question 37

steroid hormone receptor (5)

Answer 37

1. enters 2. displaces heat shock protein on receptor 3. dimerization 4. moves to nucleus and binds to DNA 5. transcription, translation, protein

Question 38

what usually keeps steroid receptors inactive

Answer 38

repressor proteins

Question 39

what is androgen insensitivity syndrome

Answer 39

when someone is unable to respond to steroid hormones | -could have a XY genotype bu XX phenotype