Pancreatic secretion

Question 1

characteristics of Pancreatic juice

Answer 1

1. High volume
2. alkaline
3. same Na+ and K+ concentrations as plasma
4. higher HCO3-concentration than plasma
5. lower Clconcentration than plasma
6. Isotonicity
7. Pancreatic lipase, amylase, and proteases

Question 2

volume of pancreatic juice is secreted per day

Answer 2

1500 ml,

Question 3

pH of the duodenal contents

Answer 3

6.0 to 7.0

Question 4

WHY pH of the duodenal contents is 7

Answer 4

Pancreatic, bile and intestinal juice neutral neutralize the gastric acid

Question 5

composition of pancreatic secretion at low flow rates

Answer 5

Na+ and Cl-

Question 6

composition of pancreatic secretion At high flow rates

Answer 6

Na+ and HCO3.

Question 7

↑ flow rate →

Answer 7

↑ bicarbonate secretion → ↑ PH

Question 8

The acinar cells of the exocrine pancreas make up

Answer 8

most of its weight (99%)

Question 9

Acinar cells produce a

Answer 9

small volume of initial pancreatic secretion, which are mainly Na+ and Cl-
2.secreted enzymes of the pancreatic juice

Question 10

Ductal cells

Answer 10

modify the initial pancreatic secretion by secreting HCO3
- and absorbing Cl- via a CI-HCO3
exchange

Question 11

epithelial cells of the ductulus secrete

Answer 11

HCO3 ions and water

Question 12

bicarbonate in panc / plasma

Answer 12

bicarbonate ion concentration can rise to as high as 145 mEq/L, a value about 5 times that of bicarbonate ions in the
plasma.

Question 13

Secretin stimulates

Answer 13

secretion of bicarbonate ions →Secretin increases cAMP in the ductular cells →thereby opens CFTR Cl− channels >causes an outflow of Cl−into the
duct lumen. →secondarily drives the activity of an adjacent antiporter that exchanges the chloride ions for bicarbonate.