VI- Digestion and Absorption Flashcards
1
Q
where Ca absorbed at
A
duodenum only
2
Q
where iron absorbed at
A
duodenum only
3
Q
where carbs absorbed at
A
duodenum and jejunum
4
Q
where fats absorbed at
A
entire small intestine
5
Q
where protein absorbed at
A
entire small intestine
6
Q
where bile salts absorbed at
A
terminal ileum only
7
Q
where vit B12 absorbed at
A
terminal ileum only
8
Q
carb digestion pathway
A
- polysaccharides digested by a-amylase @ lumen of intestine
- oligosaccharides dig by carb-ases @ brush border
- monosaccharides dig/transported by SGLT1 and GLUT5 @ brush border
9
Q
substrates of SGLT1
A
- glucose
- galactose
coupled to sodium
10
Q
substrate of GLUT5
A
fructose
11
Q
substrates of GLUT2
A
all 3 monosaccharides
-glucose, galactose, fructose
12
Q
protein digestion pathway
A
- protein from diet dig by pepsin @lumen of the stomach
- oligopeptides and amino acids dig by trypsin @lumen of intestine + peptidase @brush border
- absorbed as oligos and AAs
13
Q
amino acid absorption mechanism
A
nutrient-sodium coupled transporter
-highly functional during fed state
14
Q
oligopeptide absorption mechanism
A
- transport across membrane by H+ linked cotransporters like PEPT1
- further dig to AAs by intracellular peptidases
15
Q
lipid digestion pathway
A
- lipids aka triglycerides and cholesterol get emulsified @lumen of stomach
- FFAs, cholesterol, tri/diglycerides more emulsified with bile + pancreatic lipase + co-lipase @ lumen of duodenum
