past exam questions digestion and absorption

Question 1

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

Answer 1

1.Micelles contain bile salts and fatty acids/monoglycerides;
2.Make fatty acids/monoglycerides (more) soluble (in water)
OR
Bring/release/carry fatty acids/monoglycerides to cell/lining (of the
iluem)
OR
Maintain high(er) concentration of fatty acids/monoglycerides to
cell/lining (of the ileum);
3. Fatty acids/monoglycerides absorbed by diffusion;
4.Triglycerides (re)formed (in cells);
Accept chylomicrons form
5.Vesicles move to cell membrane;
Accept exocytosis for ‘vesicles move’

Question 2

Describe the role of micelles in the absorption of fats into the cells lining the ileum.

Answer 2

1.Micelles include bile salts and fatty acids;
2.Make the fatty acids (more) soluble in water;
3.Bring/release/carry fatty acids to cell/lining (of the ileum);

Question 3

Explain the advantages of lipid droplet and micelle formation.

Answer 3

1.Droplets increase surface areas (for lipase /
enzyme action);
2.(So) faster hydrolysis / digestion (of triglycerides / lipids);
3.Micelles carry fatty acids and glycerol /
monoglycerides to / through membrane / to
(intestinal epithelial) cell;

Question 4

Name structure Q in the diagram above and suggest how it is involved in
the absorption of lipids.

Answer 4

1.Golgi (apparatus);
2.Modifies / processes triglycerides;
3.Combines triglycerides with proteins;
4.Packaged for release / exocytosis
OR
Forms vesicles;