Absorption

Question 1

Amino acids/Glucose

Answer 1

• sodium dependent amino acid carrier protein
• diffuse across epithelial cell
• AA facilitated diffusion w/ channel protein into capillary
• sodium actively transport out of cell via Na+/K+ pump.

Question 2

Lipids

Answer 2

-MG and FA associate with phospholipids and bile salts to form micelles

Question 3

Micelle properties

Answer 3

• transport insoluble FA and MG to epithelial cell surface
• micelles break down and add to a pool of FA and MG that are dissolved in the small intestine solution surrounding cells
• non-polar so can diffuse through phospholipid bilayer
• short FA chains can diffuse directly into blood
• long FA chains recombine w/ MG and glycerol to form triglycerides in the endoplasmic reticulum

Question 4

Chylomicron

Answer 4

• triglycerides packaged within lipoproteins

Question 5

Lacteal

Answer 5

• chylomicrons transported to lacteal (lymph vessel) via exocytosis
• chylomicrons enter the bloodstream