Endocrine- peptide hormones

Question 1

peptide hormones are or aren’t water soluble?

Answer 1

are water soluble as this allows for travel through blood and target cells

Question 2

used up very quickly hence stored in secretory ??? in cytosol of endocrine cells

Answer 2

secretory granules

Question 3

peptide hormones in secretory granules are released when there is an influx of calcium in ???

Answer 3

cytosol

Question 4

peptide hormone receptors are ???-spanning with extracellular ligand-binding sites

Answer 4

membrane-spanning

Question 5

peptide hormones are NOT manufactured by which tissue?
pancreas, GI tract, Adipose tissue, Pituitary gland, parathyroid gland, hypothalamus, adrenal gland, kidneys, thyroid

Answer 5

thyroid gland doesn’t produce peptide hormones

Question 6

protein synthesis and processing: which step is missing?
transcription of mRNA → ribosomes on RER → ??? → vesicular storage → release via exocytosis

Answer 6

further processing by Golgi

Question 7

TRUE or FALSE: preprohormone refers to a peptide hormone that is synthesised from its constituent amino acids

Answer 7

TRUE, it’s the inactive form

Question 8

preproinsulin mRNA is cleaved to ??? at the RER

Answer 8

proinsulin

Question 9

proinsulin is processed in the ??? where it is cleaved to make active insulin and C-peptide

Answer 9

gogli apparatus

Question 10

can peptide hormones diffuse through the lipid bilayer?

Answer 10

no because they are water soluble whilst the lipid bilayer is not

Question 11

peptide hormones require the use of a ??? to interact with the cell membrane receptors to get their message across

Answer 11

messenger

Question 12

peptide receptors have extracellular ???-binding sites

Answer 12

ligand-binding sites

Question 13

examples of peptide-hormones binding to receptors include epinephrine, ??? and are mainly intracellular ??? messengers

Answer 13

glucagon
intracellular 2nd messengers

Question 14

G-protein coupled receptors binds ??? nucleotide and is a single polypeptide chain with 7 transmembrane helices/domains

Answer 14

guanine nucleotide

Question 15

The G-protein Receptor on the cell is the link between ligand/signalling molecule (extracellular) and ??? (intracellular)

Answer 15

G-proteins

Question 16

TRUE or FALSE: Ligand-gated ion channels open and close (are controlled) due to a binding site on the receptor

Answer 16

TRUE

Question 17

G-alpha-s protein-coupled receptors are ??? (of Adenylyl Cyclase)

Answer 17

stimulatory

Question 18

G-alpha-i protein-coupled receptors are ??? (of Adenylyl Cyclase)

Answer 18

inhibitory

Question 19

Adenylyl Cyclase is a ??? enzyme that catalyses the reaction ATP –> cAMP (a 2nd messenger)

Answer 19

membrane-bound enzyme

Question 20

cAMP (cyclic-adenosine monophosphate) is a ??? which activates the protein kinase A by binding to inactive PKA complex

Answer 20

2nd messenger

Question 21

an exmalpe of a catalytic/enzyme receptor are ??? receptors

Answer 21

tyrosine kinase receptors

Question 22

2nd messengers allow signal ??? which means cell do not need a huge amount of receptors

Answer 22

signal amplification

Question 23

1st messenger refers to peptide hormone interacting with its ???

Answer 23

receptor