[4] Digestion and Absorption Flashcards
Small Intestine Surface Area gets amplified how many times?
600x
Composition:
Sucrose
Lactose
Maltose
Glu-Fru
Glu-Gal
Glu-Glu
Carbohydrates compose what % of our diet
50-60%
What is more effective? Ptaylin or Pancreatic Amylase?
Ptyalin: 20-40%
Pancreatic Amylase: 50-80%
% Digestion
Triglycerides require _____ and _____ to become ____ and ____
Colipase and Lipase
Fatty Acids and Monoglycerides
Phospholipids require _____ to become ____ and ____
Phospholipase A2
Fatty Acids and Lysolecithin
In a normal intestine which is greater? Absorption or Secretion?
Absorption > Secretion
SCFA’s are taken up by?
Colonocytes
Fat-Soluble Vitamins
ADEK
Where are Bile Acids and Vitamin B12 absorbed?
Ileum
What do you need to properly absorb Calcium?
Vitamin D
Should you take calcium before, during, or after meals?
2 hours after
Some food can interfere with Ca uptake
What state is it easier to uptake iron in? Ferrous or Ferric?
Ferrous (Fe2+)
What can decrease iron absorption?
Tannins (Non-herbal Teas)
Phytates, wheat, and other cereals
What is the storage form of iron in the body?
Ferritin
Best site of absorption of Carbohydrates?
Duodenum
[Effect on Absorption]
- Lipid Solubility
- Size
- Presence of Special Carrier
- Electrochemical Gradient
- = +
- Smaller = +
- W/ special carriers = +
- = +
Effect of Plicae Circulares on Surface Area
x3
Effect of Villi on Surface Area
x10
Effect of Microvilli on Surface Area
x20
How is sucrose digested?
Membrane Digestion
Occurs at the immediate vicinity of the brush border
How are proteins digested?
Luminal Digestion
With proteases occuring within GI lumen