Pancreas and Endocrine

Question 1

Beta cells make up what percent of islet

Answer 1

70%

Question 2

beta cells secrete

Answer 2

insulin
proinsulin
C peptide
amylin

Question 3

alpha cells make up what percent of islet

Answer 3

20%

Question 4

alpha cells secrete

Answer 4

glucagon

Question 5

delta cells make up what percent of islet

Answer 5

~5%

Question 6

delta cells secrete

Answer 6

somatostatin

Question 7

delta cells block

Answer 7

blocks release of insulin and glucagon from nearby cells
blocks release of other gastric hormones and growth hormones

Question 8

where are beta cells mainly found

Answer 8

middle

Question 9

where are alpha and delta cells mainly found

Answer 9

periphery

Question 10

how does blood flow in islet

Answer 10

flows from center outwards

Question 11

does blood flow deliver somatostatin to beta cells

Answer 11

no

Question 12

what junctions connect cells to allow for communication and regulation of hormone release in islet of langerhands

Answer 12

tight junctions
gap junctions

Question 13

parasympathetic stimulation for islet of langerhans

Answer 13

parasympathetic stimulation via vagus nerve
cholinergic to increase insulin –> primes pancreas

Question 14

sympathetic stimulation for islet of langerhans

Answer 14

alpha adrenergic –> inhibitory

Question 15

what primes pancreatic beta cells

Answer 15

incretins

Question 16

definition of incretins

Answer 16

peptides released by intestinal cells that augment beta cell response to oral glucose stimulus

Question 17

examples of incretins

Answer 17

chyolecystokinin
glucagon-like peptide 1 (GLP-1)
gastric inhibitory polypeptide (GIP)

Question 18

What is GLP-1 broken down by

Answer 18

dipeptidyl-peptidase 4

Question 19

where is pre-proinsulin made

Answer 19

rough endoplasmic reticulum

Question 20

is pre-proinsulin active

Answer 20

no, it is nonactive

Question 21

order for pre-proinsulin

Answer 21

pre b c a post

Question 22

biologic activity proinsulin

Answer 22

1% in comparison to insulin

Question 23

parts of proinsulin

Answer 23

b c a

Question 24

proinsulin is transported where to create insulin

Answer 24

from RER to golgi apparatus

Question 25

ratio of insulin to c peptide release into systemic circulation

Answer 25

1:1 ratio

Question 26

what percent of insulin is removed in first-pass through portal circulation

Answer 26

60%

Question 27

where is c peptide excreted

Answer 27

in urine it is not extracted by liver in first pass!!!

Question 28

function of amylin

Answer 28

inhibits glucagon release decreases gastric emptying acts centrally to decrease appetite

Question 29

what are the two ways that pro glucagon can be processed

Answer 29

alpha cells in the pancreas neuroendocrine L cells in the intestines

Question 30

alpha cells in the pancreas create

Answer 30

glucagon

Question 31

neuroendrocrine L cells create

Answer 31

GLP-1

Question 32

function of GLP-1

Answer 32

stimulates insulin synthesis and release

Question 33

glycogenesis

Answer 33

formation of glycogen

Question 34

glycolysis

Answer 34

metabolic pathway that converts glucose to create energy

Question 35

glycogenolysis

Answer 35

breakdown of glycogen to glucose

Question 36

gluconeogenesis

Answer 36

synthesis of new glucose from noncarb precursors

Question 37

when does glycogenesis occur

Answer 37

when glucose levels are sufficient enough to allow excess glucose to be stored in liver and skeletal muscle

Question 38

function of glycogenolysis

Answer 38

increases blood glucose levels and provides energy

Question 39

function of gluconeogesis

Answer 39

provides glucose when dietary intake is insufficient

Question 40

glucose transport is primarily controlled by

Answer 40

glucose transporters (GLUT)

Question 41

GLUT allows glucose into the cell via

Answer 41

facilitated diffusion

Question 42

Where are insulin independent GLUT transporters found

Answer 42

liver brain RBC retina kidney nervous tissue

Question 43

what is the catalyst that converts glucose to G-6-P through phosphorylation

Answer 43

hexokinase isoenzymes (HK)

Question 44

what is the first step in the utilization of glucose for storage for energy metabolism

Answer 44

conversation of glucose to G-P-6 via hexokinase isoenzymes through phosphorylation

Question 45

phosphorylation of glucose effect ---

Answer 45

makes it difficult for it to leave the cell

Question 46

where are sodium dependent glucose transports (SGLT) found

Answer 46

intestinal mucosa proximal tubule of nephron

Question 47

which sodium dependent glucose transporter is found in intestinal mucosa

Answer 47

SGLT1

Question 48

which sodium dependent glucose transporter is found in proximal tubule of nephron

Answer 48

SGLT2

Question 49

SGLT2 allows for

Answer 49

reabsorption of glucose

Question 50

Insulin secretion is stimulated by

Answer 50

glucose (primarily) amino acids and ketoacids (weakly) via the citric acid cycle

Question 51

insulin secretion is caused by (think about ions)

Answer 51

closure of K+/ATP channel and opening of voltage-gated calcium channel

Question 52

how many sulfonylurea receptors are present on K+/ATP channel

Answer 52

4

Question 53

function of sulfonylurea receptors on K+/ATP channel

Answer 53

they stimulate closure --> increase insulin release