Notes: Small Intestine Wednesday 1-6-10. (1) Overall Function Absorb nutrients from stomach chyme...
-
Upload
julius-ramsey -
Category
Documents
-
view
212 -
download
0
Transcript of Notes: Small Intestine Wednesday 1-6-10. (1) Overall Function Absorb nutrients from stomach chyme...
Notes: Small Intestine
Wednesday 1-6-10
(1) Overall Function
Absorb nutrients from stomach chyme
Metabolize ALL Proteins and Lipids
Leave only waste and water
(2) Regions
Duodenum: (First Chamber)– Approximately 10in long
Jejunum: (Middle Section)– Approximately 7-8ft long
Ileum: (Last Section)– Approximately 12ft long
(3) Duodenum
Secretes Bile, Pancreatic Juice & Bicarbonate:– Bile = Yellow-green solution produced by the
liver, stored in the gallbladder. – Pancreatic Juice = Solution produced by the
pancreas, stored in the pancreas.– Bicarbonate = pH balancing compound found
in the blood.
Metabolize all remaining proteins and lipids.
(4) Bile
Produced by liver, Stored by Gallbladder Contains:
– Bile Salts– Waste Pigments (bilirubin)– Cholesterol & Phospholipids
Function: Emulsify lipids so that they are dispersed throughout water, and can be easily absorbed.
(5) Pancreatic Juice
Produced by pancreas Contains:
– Carboxypeptidase (Protein Enzyme)– Chymotrypsin (Protein Enzyme)– Amylase (Carbohydrate Enzyme)– Lipases (Lipid Enzymes)– Nucleases (Nucleic Acid Enzymes)
Function: Metabolize all remaining biomolecules.
(6) Bile & Pancreatic Juice Secretion
Lipids & Proteins Release of CCK (cholecystokinin) into bloodstream
CCK stimulates release of bile + pancreatic juice Out Sphincter of Oddi
(7) Bicarbonate
HCO3
Used to maintain pH balance within cells (and water systems).– Neutralizes acidity of chyme coming
from stomach
Secreted from Brunner’s Glands along Duodenum Walls.
(8) Jejunum
Smooth Muscle with millions of microvilli:– Microvilli Absorb Nutrients– Nutrients directly deposited in blood stream– Folds in between are called “Crypts of Lieberkuhn”
Crypts of Lieberkuhn:– Secrete Lysozymes to eliminate any foreign bacterial
cells– Secrete Muccin to lubricate and dissolve remaining
food stuff
(9) Ileum
Smooth muscle like Jejunum:– Contains Microvilli– Absorbs all left over nutrients– Directly deposits into bloodstream
Remaining “stuff” = waste