Lecture 40- Nonfermentative Digestion and Absorption Flashcards
What are the circular constrictions found in the intestines
Plicae circulares
Microvilli prjections form th
Brush border
What connects the apical part of enterocytes
Tight junctions
What part of the small intestine is made of glycoproteins that digests disaccharides and small proteins
Glycocalyx
What is the tin layer of water that flows over the intestinal surface to prevent lipid absorption
Unstirred water layer
What is the main mechanism of macrobutrient breakdown
Hydrolysis
What type of bonds are present in starch
alpha 1-4 glycosidic bonds
What bond is present in fiber that cannot be digested without fermentation
beta 1-4 glycosidic bonds
Does amylase finction in lumenal digestion of membranous digestion
Lumenal
What peptide form is more easily absorbed
di and tripeptides
What section of the GI system digests the most fat?
The small intestine
4 phases of lipid assimilation
Emulsification
Hydrolysis
Micelle formation
Absorption
What bile micelle quality allows it to pass through the unstirred water layer?
Hydrophilic outside
Lipids packaged within enterocytes with cholesterol
Chylomicron
Where do chylomicrons travel to
Lymphatic circulation, then dumped into the vena cava
What disease is caused bypancreatic acinar atrophy resulting in fat in feces and lack of absorbion
Exocrine pancreatic insufficiency
Glucose is passively absorbed into the apical portion of the cell using cotransport with
Na
In enteric cells-
H+ is excreted to absorb-
Bicarb is excreted to absorb-
Na+ and CL-
Where do monogastrics produce B12
The colon (not absorbed)
Where is most B12 absorbed
Ileum
What transports B12
Intrinsic factor in the intestins, transcobalamin systemically
