pancreas

Question 1

what type of organ is the pancreas

Answer 1

secretory

Question 2

4 superior anterior portions of pancreas (right to left )

Answer 2

head, neck, body, tail

Question 3

inferior anterior portion of pancreas connected to head

Answer 3

uncinate process (hook-like)

Question 4

what do smaller pancreatic ducts all converge into

Answer 4

larger pancreatic ducts

Question 5

what do larger pancreatic ducts combine with and where

Answer 5

common bile duct at the ampulla of Vater

Question 6

what does the ampulla of Vater drain into and where

Answer 6

duodenum at sphincter of oddi

Question 7

bifurcation of common bile duct

Answer 7

left to cystic duct (gall bladder), right to hepatic ducts (left and right lobes of liver)

Question 8

where does head of pancreas sit

Answer 8

C-shaped part of duodenum

Question 9

where does tail of pancreas sit

Answer 9

hylem of spleen

Question 10

where does perfusion of pancreas come from

Answer 10

branches of superior mesenteric artery and celiac trunk

Question 11

where does drainage of pancreas go to

Answer 11

hepatic portal vein to liver then systemic circulation

Question 12

how much of pancreas is exocrine acini cells and supporting cells (duct cells)

Answer 12

98%

Question 13

what are ducts lined with

Answer 13

columnar epithelia

Question 14

3 features of islets of endocrine tissue

Answer 14

not connected to ducts, highly vascularised, secrete hormones into blood

Question 15

function of connective tissue

Answer 15

provides structural support

Question 16

what do zymogen-secreting acinar cells cells contain and where

Answer 16

zymogen granules towards apical membrane

Question 17

what is zymogen

Answer 17

inactive enzymes (mainly protease to prevent degradation of cells, as well as lipase and amylase) and enzyme inhibitors

Question 18

where do secreted enzymes go from acini

Answer 18

into smaller ducts then into larger ducts

Question 19

function of bicarbonate-secreting duct cells

Answer 19

dilute enzymes and carry into pancreatic duct and duodenum

Question 20

most abundant cells in islets of Langerhans

Answer 20

insulin-secreting B-cells (70%)

Question 21

second most abundant cells in islets of Langerhans

Answer 21

glucagon-secreting a-cells (20%)

Question 22

third most abundant cells in islets of Langerhans

Answer 22

somatostatin-secreting d-cells (10%)

Question 23

what is atop of all cells in islet of Langerhans

Answer 23

pancreatic capillaries

Question 24

function of pancreatic capillaries

Answer 24

recieve hormones from surrounding cells and releasing into bloodstream for local and systemic effects

Question 25

2 types of exocrine cell

Answer 25

acinar, duct

Question 26

components of acinar cells to produce enzymes

Answer 26

high in Goligu apparatus; rough ER and nucleus towards larger basolateral membrane; zymogen granules towards apical membrane

Question 27

arrangement of functional subunit of exocrine pancreas

Answer 27

acinar cells towards terminal end of duct to allow secretion of enzyme-rich, viscous, low-volume fluid into terminal duct from acinar cells via exocytosis, using calcium as a second messenger; duct cells line terminal duct

Question 28

what do duct cells do to fluid secreted by acinar cells

Answer 28

modify it by secreting bicarbonate-rich (via carbonic anhydrase), high-volume, watery fluid via membrane channels, relying on ion gradients

Question 29

significance of centroacinar cells found between duct cell and acinar cell

Answer 29

internal cellular characteristics of both duct cells and acinar cells, but act more like duct cell

Question 30

purposes of bicarbonate secretion from duct cells

Answer 30

helps mobilise enzyme-rich component of pancreatic juice so it moves into duodenum, able to neutralise acid chyme

Question 31

innervation of duct cells

Answer 31

hormonal only

Question 32

innervation of acinar cells

Answer 32

hormones and CNS

Question 33

when does pancreas begin to develop

Answer 33

day 35-39

Question 34

what 2 sites does the pancreas develop from

Answer 34

ventral pancreatic bud, larger dorsal pancreatic bud

Question 35

where can the duodenum be differentiated from

Answer 35

stomach

Question 36

where does the ventral pancreatic bud sprout from

Answer 36

liver bud

Question 37

where does dorsal pancreatic bud sprout from

Answer 37

duodenum

Question 38

what does the endoderm now start to develop into at day 40-55

Answer 38

branched tubules, which later develop into ducts

Question 39

what are the ducts connected to

Answer 39

acini (exocrine portion of pancreas)

Question 40

where do islets of langerhans arise from

Answer 40

duct branchpoints

Question 41

fate of islets of langerhans

Answer 41

disconnect from ducts to form discrete islands of highly vascularised endocrine tissue amongst parnechyma of exocrine glandular tissue

Question 42

what happens at the 6 week mark

Answer 42

gut tube undergoes primary rotation

Question 43

what is the outcome of the duodenum twisting on the pancreas

Answer 43

ventral pancreas and biliary system moves towards dorsal pancreas (allows duodenum to form C-shape also)

Question 44

what happens on day 56

Answer 44

dorsal and ventral pancreas fuse together

Question 45

what does the dorsal pancreatic duct normally fuse with, but what can it also be connected to

Answer 45

common bile duct, but can be connected to gut as accessory pancreatic duct

Question 46

what does the ventral pancreatic duct become

Answer 46

uncinate process of mature pancreas; major route of drainage into small intestine

Question 47

what is the ventral pancreatic duct already connected to

Answer 47

biliary tree via common bile duct (gall bladder via cystic duct, liver via hepatic duct), become the major pancreatic duct