4A & 4B- S.I. A&P Flashcards
What is the beginning and end of the Duodenum? How long is it?
Pyloric Valve—> DuodenoJejunal Flexure….10-12in
Which stomach enzyme is inactivated in the duodenum because of the increased pH?
Pepsin!
What are the borders of the Jejunum? How long is it?
the DuodenoJejunal Flexure—->ileum…8ft long
What are the borders of the ileum? How long is it?
From the end of the jejunum to the IleoCecal Valve…12ft long
What is the anatomy of the mucosal layer of the S.I. from largest to smallest?
MacroVillae(Plicae Circulares—>villi—>microvilli
What level of SI anatomy would I find goblet cells? What about crypts?
Goblet Cells: Lined on a villus….Crypts in between villi
Which SI cells possess a layer of closely packed microvilli , brush border enzymes, and transporters?
Surface Absorptive Cells
What is the fancy full name for the crypts of the SI?
Crypts of Liber-Kuhn
What are the mucus producing cells of the SI?
Goblet Cells
Which SI cells secrete CCK, Secretin, and GIP?
EnteroEndocrine Cells (DNES/APUD cells)
Which SI cells divide to replace themselves and other types of epithelial cells?
Regenerative Cells
Which SI cells secrete the antibacterial enzyme lysozyme and other antibacterial agents?
Pan-eth Cells
What epithelial cell type composes the majority of enterocytes in the SI?
Simple Columnar Epithelial cell
What are the 2 end products of Pancreatic Amylase digestion on polysaccharides (starch/glycogen)?
1.Disaccarides 2.Oligosaccharides
Disaccharides are degraded by a group of ______ ______ ________ called __________.
Brush Border Enzymes called DisaccharidASES (maltase, lactase, sucrase, alpha-dextrin)
Glucose and galactose are absorbed (via _______ _______ transport) through a ___-dependent cotransporter known as _____.
secondary active…Na+…..SGLT1
Fructose enters by _______ _______ via ______ ______ ___ (_____) that does not require ___.
facilitated diffusion…..glucose transporter 5 (GLUT5)….Na+
ALL monosaccharides are transported out of the enterocytes and into the capillaries by ____’s (via ______ ______).
GLUT2’s…(via facilitated diffusion)
What causes lactose intolerance? Why does gas result? Why does bloating and diarrhea result?
Caused by no Lactase. Gas caused by bacterial fermentation of lactase. Bloating and diarrhea caused by water pulled into G.I. tract post bacterial ingestion.
Do we digest protein in the mouth?
Nope!
What enzyme is working to break down protein in the stomach?
Pepsin
Where does the BULK of protein digestion occur? What are the two main enzyme groups at work here?
The BRUSH BORDER of the S.I. 1.AminoPeptidAses 2.Proteases(Active Pancreatic Enzymes)
REVIEW: what are the 4 pancreatic enzymes involved in breaking down proteins to oilgopeptides in the SI?
1.Trypsin 2.Chymotrypsin 3.CarboxyPeptidases 4.Elastase
What is the size limit for bringing peptides/AA’s into an enterocyte?
Tripeptides, Dipeptides, and single AAs can enter the cell
What type of co transporter helps get PEPTIDES/AAs into the enterocyte (SOME of the time)? What is the other option?
Glucose co-transporters…other option is facilitated diffusion
What is the FIRST step in Lipid digestion? What is the main players here?
Emulsification…Major player BILE ACIDS and Lecithin
What do pancreatic lipase and coLipase break down triacylglycerides into?
a monoglyceride and 2 free fatty acids
What is the difference between a chylomicron and a micelle?
Chylomicron=triacylglycerols into lacteals(lymph)…vs….Micelle=monoglycerol and free fatty acids going into an enterocyte
Why do chylomicrons enter a lacteal instead of a blood vessel?
SIZE! capillaries are too small for the chylomicron.
Once the chylomicrons enter the lymphatic circulation, they are transported upward through the ________ and emptied into the venous circulation at the juncture of the _______ and _______ veins.
thoracic duct……jugular and subclavian veins
______ usually occurs within an hour after eating a fatty meal. _________ have a short half-life (< 60 min), so the plasma usually becomes clear within a few hours.
Lipidemia….Chylomicrons
Chylomicrons are removed from the blood as they pass through the capillaries of ________ and the ______. Both contain large quantities of __________.
adipose tissue and the liver…lipoprotein lipase
Where is lipoprotein lipase especially active?
The capillary endothelium
What are the 5 classes of lipoproteins? Which one is the ONLY type made in enterocytes?
- Chylomicrons (ONLY one made in enterocytes) 2.VLDL 3.IDL 4.LDL 5.HDL
_____ are the most effective drugs currently in use for treating elevated LDL-C. What enzyme are they targeting?
Statins..HMG CoA REDUCTASE inhibitors!!
What is the #1 adverse side effect of Statins? What are the 3 subcategories? WHAT do you see/not see in the blood?
MyoPathy…1.Myalgia(muscle weakness WITH OUT Creatnine Kinase in the blood) 2.MyoSitis (elevated CK in the blood) 3.RAB-DOH (RhabdoMyoLYSIS)
What are the 4 things you find in the blood/urine to diagnose Rhabdomyolysis?
Creatnine Kinase….creatinine…dark urine and myoglobinuria
What is the % of Pt taking a Statin to report MyoPathy?
10%
Risk factors for _______ ______ include being elderly, small size, high statin dose, liver or renal disease, diabetes, uncontrolled hypothyroidism, and interacting medications.
statin myopathy
What is the drug aimed at increasing HDL? What does this drug REDUCE?
Niacin..Also reduces VLDL production
What are the 3 preparations of Niacin?
1.Immediate(crystalline) Release 2.Sustained Release 3.No-flush
What are the two other names for Niacin?
Nicitinic Acid, Vitamin B3
Niacin can cause a ___-___% increase in HDL-C
15-35% increase in HDL-C
What can you do to combat the harmless side effect of the warm flash of Nacin?
Its a PROSTAGLANDIN mediated effect, so you can block them with ASA or NSAIDs 30-45min before!
The _______ are among the oldest of the hypolipidemic drugs and sometimes considered the _____ since they are not absorbed from the intestine.
Bile Acid Binding Resins…safest
BOOM! What are the two resins available in Granular form?
Cole-Stid and Quest-Ran
BOOM! What are the two resins available that are tablets mixed with water?
Cole_Stid and Wel-Chol
What are the two methods of action for Bile Acid Resins?
- Decreased emulsification of fat 2.No bile acid reabsorption (liver then uses cholesterol to make more bile!)
What do Bile Acid Resins do to LDL, HDL, and Triacylglyceride levels in the blood?
REDUCE LDL, no effect on HDL nor TAGs
What are the 9 adverse effects of Bile Acid Resins? How can you combat them?
1.Constipation 2.Bloating 3.Abdominal Distention 4.Pain 5.Flatulence 6.Nausea 7.Vomiting 8. Dyspepsia 9. Oily Anal Leakage…Combat with FIBER supplement
What are the 7 drugs and substances that Bile Acid Resins can bind to?
1.Fat Sol Vitamins 2.Folate 3.ThiAZides 4.TetraCyclines 5.Warfarin 6.Propanolol 7. Penicillin
All H20 absorption in the small intestine is ______ and secondary to ______ movement.
passive…solute
Most K+ is absorbed passively when luminal [K+] rises because of absorption of water (_________).
Solvent drag
Calcium absorption occurs in the ________ & _______ and is primary regulated by ________ (_____________)
duodenum & jejunum….vitamin D3 (1, 25 dihydroxycholecalciferol)
What does absorption of Calcium stimulate the production of in enterocytes?
CalBindIns (Calcium binding proteins)
How are fat soluble vitamins absorbed? What about water soluble?
Fat-soluble= like other lipids…Water sol=SIMPLE DIFFUSION
Which water soluble vitamin requires Intrinsic Factor (IF) for normal absorption? WHERE do these get absorbed?
B12(Cobalamin/CBL)..Absorbed in the ileum
What becomes deficient with atrophy of the gastric mucosa?
Vitamin B12
Where are the three places I can find Peristaltic Contractions?
1.Esophagus 2.Stomach 3.Small Intestine
How long does it take for chyme to move through the entire SI?
3-5 hours
REVIEW:Which autonomic digestive process helps with mechanical digestion of food?
Segmentation
