Small intestine

M3O14. What are the 8 cells of the small intestine?

1. microvilli and villi
2. enterocytes
3. capillaries
4. goblet cells
5. lacteals
6. stem cells
7. crypt cells
8. endocrine cells

M3O14. __ and _ increase surface area.

microvilli and villi

M3O14. __ transport nutrients and ions.

enterocytes

M3O14. transport most absorbed nutrients.

capillaries

M3O14. secrete mucus.

Goblet cells

M3O14. __ transport most fats to the lymph.

lacteals

M3O14. divide to replace damaged cells.

stem cells

M3O14. _ secrete ions and water.

crypt cells

M3O14. _ secrete hormone.

endocrine cells

M3O14. What are the 3 distinguishing features of the small intestine?

1. Villi
2. Plica
3. Circular and longitudinal muscle

M3O15. facilitates movement of chyme ultimately into the large intestine.

Peristalsis

M3O15. to mix the chyme with digestive secretions to aid in digestion and absorption.

Segmentation

M3O15. ___ ___ __ waves in the stomach → large intestine that clears food from the GI tract between meals.

Migrating Motor Complex

M3O15. What are the exocrine secretions of the small intestine and pancreas?

1. Bicarbonate

2. Mucous

3. Pancreatic enzymes

4. Bile (liver and gall bladder)

M3O16. The _ produces enzymes that help to digest proteins.

pancreas

M3O16. What does the pancreas secrete?

insulin and glucagon

M3O16. What is the function of the pancreas?

regulate glucose level in the blood and somatostatin

M3O16. The pancreas creates ____ to

• break down foods

• empty into the duodenum.

pancreatic enzymes

M3O16. _ concentrates bile from the liver.

Gall bladder

M3O16. What does the gall bladder secrete?

bile

M3O16. What is the function of the gall bladder?

helps digest fats

M3O16. The gall bladder releases bile into the duodenum through the

biliary tract.

M3O16. The ___ receives secretions from the gallbladder, liver, and pancreas.

common bile duct

M3O16. Regulation of the bile and pancreatic secretions entering the duodenum is controlled by the _____ or ____

Hepatopancreatic Sphincter or Sphincter of Oddi

M3O16. _ helps to further digest food from the stomach and absorbs nutrients and water to be used by the body.

duodenum

M3O16. What does the duodenum secrete?

sucrose, maltase, lactase, and peptidase

M3O16. What is the function of the duodenum?

to further break down food

M3O17. Exocrine pancreas is primarily regulated by _____activation

PNS

M3O17. Cholecystokinin (CCK) regulates secretion of ___ and _.

enzymes and bicarbonate

M3O17. Secretin regulates secretion of .

bicarbonate

M3O18. What is the key enzyme involved in how bicarbonate is produced?

Carbonic Anhydrase (CA)

M3O18. What is the purpose of bicarbonate?

neutralize H+ secreted by the stomach

M3O18. Bicarbonate is a _ (acid/base).

base

M3O19. Why are pancreatic protease enzymes packaged as zymogens?

It can destroy proteins of the pancreas/tissues

-when activated

M3O19. Trypsinogen is activated by ___ in the brush border or microvilli into Trypsin

enteropeptidase

M3O19. Trypsin activates zymogens into _ _.

activated enzymes

M3O19. What are the 4 zymogens that are used for protein digestion?

1. Trypsinogen
2. Chymotrypsinogen
3. Procarboxypeptidases
4. Proelastase

M3O20. Where is gastrin (g cells) secreted?

stomach

M3O20. Where does gastrin act?

ECL cells and parietal cells

M3O20. Gastrin (inhibits/stimulates) gastric acid secretion and mucosal growth.

stimulates

M3O20. What are the 3 stimuli for release of gastrin?

1. peptides
2. amino acids
3. neural reflexes

M3O20. Where is Cholecystokinin (CCK) produced?

(ENS) neurons and endocrine cells of duodenum and jejunum

M3O20. Where does Cholecystokinin (CCK) act?

gallbladder, pancreas, and stomach

M3O20. _ promotes satiety (feel full) by stimulating vagal afferent fibers that activate brainstem centers

Cholecystokinin (CCK)

M3O20. Cholecystokinin (CCK) ___ (inhibits/stimulates) gallbladder contraction to release bile salts

stimulates

M3O20. Cholecystokinin (CCK) ___ (inhibits/stimulates) gastric emptying.

inhibits

M3O20. Cholecystokinin (CCK) ___ (inhibits/stimulates) stomach and small intestine motility to allow for fat digestion.

inhibits

M3O20. Cholecystokinin (CCK) ___ (inhibits/stimulates) exocrine pancreatic enzyme secretion.

stimulates

M3O20. Cholecystokinin (CCK) ___ (inhibits/stimulates) gastric acid secretion.

inhibits

M3O20. What is the stimuli for release of Cholecystokinin (CCK)?

fatty acids and some amino acids

M3O20. Where is secretin secreted?

specialized endocrine cells in the duodenum

M3O20. Where does secretin act?

pancreas and stomach

M3O20. Secretin __ (stimulates/inhibits) gastric emptying.

inhibits

M3O20. Secretin __ (stimulates/inhibits) gastric motility.

inhibits

M3O20. Secretin __ (stimulates/inhibits) bicarbonate secretion.

stimulates

M3O20. Secretin __ (stimulates/inhibits) gastric acid secretion from parietal cells.

inhibits

M3O20. What is the stimuli for release of secretin?

acidic chyme in small intestine

M3O20. Where is motilin secreted?

endocrine from duodenum

M3O20. Where does motilin act?

gastric and intestinal smooth muscle

M3O20. Motilin (stimulates/inhibits) migrating motor complex that clears the intestine of undigested food.

stimulates

M3O20. Food intake (stimulates/inhibits) the migrating motor complex.

inhibits

M3O20. What is the stimuli for release of motilin?

fasting

M3O20. Where is Gastric Inhibitory Peptide (GIP) secreted?

endocrine in duodenum

M3O20. Where does Gastric Inhibitory Peptide (GIP) act?

beta cells of pancreas

M3O20. Gastric Inhibitory Peptide (GIP) _ (stimulates/inhibits) gastric emptying.

inhibits

M3O20. Gastric Inhibitory Peptide (GIP) _ (stimulates/inhibits) insulin release.

stimulates

M3O20. Gastric Inhibitory Peptide (GIP) _ (stimulates/inhibits) gastric acid secretion.

inhibits

M3O20. What is the stimuli for release of Gastric Inhibitory Peptide (GIP)?

glucose, fatty acids, and amino acids in the small intestine

M3O20. Where is Glucagon-like peptide-1 (GLP-1) secreted?

endocrine from duodenum

M3O20. Where does Glucagon-like peptide-1 (GLP-1) act?

endocrine pancreas

M3O20. Glucagon-like peptide-1 (GLP-1) _ (stimulates/inhibits) gastric function.

inhibits

M3O20. Glucagon-like peptide-1 (GLP-1) _ (stimulates/inhibits) insulin release.

stimulates

M3O20. Glucagon-like peptide-1 (GLP-1) _ (stimulates/inhibits) glucagon release.

inhibits

M3O20. What is the stimuli for release of Glucagon-like peptide-1 (GLP-1)?

mixed meal that includes carbohydrates or fats in the lumen

M3O20. Erythromycin, an antibiotic that mimics motilin, (increases/decreases) gastric motility (prokinetic)

increases

M3O20. _ increase insulin secretion for type 2 diabetes

GLP-1 receptor agonists

M3O20. GLP-1 receptor agonists (stimulates/inhibits) food intake.

inhibits

M3O20. ___ and ____ help weight loss by suppressing appetite within the hypothalamus and inducing peripheral satiety by reducing gastric emptying, thus diminishing calorie intake.

Dual GIP and GLP-1 receptor agonists

M3O20. _ inhibit DPP-4 activity in peripheral plasma, which prevents the inactivation of the incretin hormone glucagon-like peptide (GLP)-1 and GIP for type 2 diabetes.

Dipeptidyl Peptidase-4 (DPP-4) inhibitors

M3O21. Complex carbohydrates (starches) need to be broken down into ____ before absorption into small intestinal cells

monosaccharides

M3O21. Starches are broken down by ptyalin and pancreatic __ into maltose

amylase

M3O21. Maltose is broken down by intestinal _ into glucose

maltase

M3O21. Salivary and pancreatic amylase breaks starches down into .

disaccharides

M3O21. are brush border enzymes that break down the disaccharides to monosaccharides that can be absorbed.

Disaccharidases

M3O21. Glucose is transported by ___ through the brush border from the lumen of the intestine.

SGLT-1

M3O21. Fructose is transported by ___ through the brush border from the lumen of the intestine.

GLUT5

M3O21. Galactose is transported by _ through the brush border from the lumen of the intestine.

SGLT-1

M3O21. Glucose, Galactose, and Fructose are transported by ___ into bloodstream from the brush border

GLUT2

M3O22. Large proteins are broken down by ___ and __ in the stomach and small intestine.

exopeptidases and endopeptidases

M3O22. ___ clip terminal amino acid from peptide chain.

Exopeptidase

M3O22. _ clips internal sequences of peptide chain.

Endopeptidase

M3O22. Inactive enzyme until it is released into the small intestine to be activated.

Zymogen

M3O23. __ is degraded by salivary amylase to dextrins and oligosaccharides in the mouth.

starch

M3O23. Dextrins and oligosaccharides are degraded by _ to lactose, maltose, and sucrose.

pancreatic amylase

M3O23. Lactose, maltose, and sucrose are degraded by _ __ to galactose, glucose, and fructose in the small intestine

brush border enzymes

M3O23. Galactose, glucose, and fructose are the absorbed by capillaries in the villi and transported to the liver by the _.

portal vein

M3O23. Proteins are degraded by ___ in the presence of HCl to proteoses and peptones in the stomach.

pepsin

M3O23. Proteoses and peptones are degraded by pancreatic enzymes (, , and ) to small polypeptides and dipeptides in the small intestine

trypsin, chymotrypsin, and carboxypeptidase

M3O23. Small polypeptides and dipeptides are degraded by _ _ into amino acids in the small intestine.

brush border enzymes

M3O23. Amino acids are absorbed by capillaries in the villi and transported to the liver by the _

hepatic portal vein