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AP Resources - Pancreas (more of digestion)

Pancreas-secretes 2 classes of things:

 

Pancreatic bicarbonate: 

 

exocrine portion secretes a whole host of digestive enzymes-4 major classes of protiolitic enzymes: enzymes that brk down proteins:

1.

2.

3.

4.

These break proteins down to the: __________and__________

 

-border brush enzymes break them down to the ___________necessary to be absorbed across _____________

 

-dipeptidases-

1.

2.

3.

 

2 factors that cause pancreas to secrete these enzymes:

 

1.

2.

 

Secretin

 

CCK 

 

-Bacteria is very active here-

1.

2.

3.

 

-Defecation Reflex

 

Break down

 

-Carbohydrates-

 

Monosaccharide (glucose), disaccharides (sucrose, lactose, maltose), polysaccharides (3 or more monosaccharide-starch, glycogen, cellulose)

 

Cellulose

 

Polysaccharides and disaccharides

 

Chemical Breakdown-mouth with salivary amelase(5-10%)-no break down in the stomach-small intestine(pancreatic amelase)breaks down to disaccharide level-border brush enzymes break down to monosaccharide level-absorbed by active transport across duodenal mucosa and early part of jujenum-absorb thru into absorptive cells and into CT lamina propria-pass into portal blood-{drain cap of DS into the cap of liver by hepatic portal vein}-isomers go to liver-liver converts isomers of glucose into glucose-releases it by hepatic vein-into inferior vena cava-to all parts of the body-blood glucose increases-

 

-insulin is released:

1.

2.

 


-Lipids-

 

-triglycerides released into Digestive System (show up as large blobs of fat)

 

-Bile ___________-pancreatic lipase______ -bile salts form micells-

(Bile salts-one end is hydrophyllic and one end is hydrophobic)

 

-lipids will pass thru-emulsified fat(micells)-travel to intestinal mucosa-fat will diffuse across cell membrane(fat is nonpolar, membrane is phosolipids)-dissolved into cell-bile salt is left on outside and reabsorbed by the ileum-carried into blood stream back to liver-liver uses it to create more bile

 

Fat moves across and is reassembled into tryglycerides in intestinal absorptive cell-packaged as lipoproteins for transport (because you can’t put fat into watery substance, so surround it with polar protein coat)-absorbed into lacteal-returned to blood stream at subclavian vein-

1.

2.

Without these: body can’t produce:

 

Low density-

 

-contributors:

 

High density

 

-Proteins-

 

-no breakdown in _______

-break down in __________

-acid_____________________

-actual digestion________

 

Pepsin(10-20%)-break down to poly and dipeptides-small intestine(tripsin, chymatripsin, elastase, carboxypeptidase-break down to dipeptide levels—border brush enzymes break(dipetidases)break down to amino acid level—individual amino acids are actively transported across intestinal mucosa-absorptive cells dump into portal circulation-transport to liver-growth hormone allows movement into cell-

 

-Water-

 

-________ of water is taken into DS a day

-________ is water that we drink

-rest comes from the food we eat

 

92% water is absorbed 

6-7%

-converts chyme

1-2%-

 

-Minerals-

 

-transported by: