Lipid Digestion/Absorption

Question 1

How do micelles help lipid absorption

Answer 1

Fatty acids more soluble in water
Carry fatty acids to epithelial cells
Maintain higher concentration of fatty acid compared to epithelial cells
Fatty acid released from micelle and enter epithelial cell via simple diffusion

Question 2

Why do fatty acids enter by simple diffsuon

Answer 2

Non polar
So can dissolve and diffuse through phospholipid bilayer

Question 3

Describe how digested lipids are absorbed and transported to ileum

Answer 3

• micelles made of bile salts fatty acids and glycerol
• micelle carry fatty acid to epithelial cell of ileum
• fatty acid absorbed into cells of ileum by simple diffusion
• triglycerides formed
• vesicles removed exocytosis

Question 4

Describe the importance of micelles in absorption lipids into the epithelial cells

Answer 4

-micelles made up of fatty acid glycerol and bile salts
- micelles make fatty acids soluble in water
- micelles carry fatty acids to epithelial cells of ileum
- fatty acids realised from micelle and absorbed into cell via simple diffusion

Question 5

When lipids are digested the form small droplets and micelles name the advantage

Answer 5

1. Lipid droplets increase surface area
2. Speeds up hydrolysis
3. Micelles bring fatty acids to epithelial cells

Question 6

How is Golgi apparatus involved in absorption of lipids

Answer 6

Modifies triglycerides
Combine proteins with triglycerides to form chylomicrons
Packaged into vesicles

Question 7

Describe the processes involved in the absorption and transport of digested lipid molecules from the ileum into lymph vessels.

Answer 7

1. Micelles contain bile salts, fatty acids, monoglycerides
2. Make fatty acid soluble in water
   3.carry monoglycerides to cell
3. Fatty acids/monoglycerides absorbed by diffusion,
   Reject if absorbed by facilitated diffusio
4. Triglycerides (re)formed
5. Vesicles move to cell membrane