To study lipid digestion, a researcher placed a tube into the small intestine of a healthy volunteer. The volunteer was fed a liquid meal containing triglycerides through the tube. The researcher withdrew samples of the intestinal contents at specific time intervals.
The concentrations of triglycerides and fatty acids in the samples were measured, as shown in Table 1.
Table 1
| Sample | Time of collection after meal / min\text{min}min | Concentration of fatty acids / mg cm−3\text{mg cm}^{-3}mg cm−3 | Concentration of triglycerides / mg cm−3\text{mg cm}^{-3}mg cm−3 |
|---|---|---|---|
| A | 30 | 1.9 | 0.8 |
| B | 60 | 2.7 | 0.0 |
Use your knowledge of lipid digestion to explain the differences in the results for samples A and B shown in Table 1. Assume that no absorption had occurred.
Immediately after collection, the researcher heated the samples to 80∘C80^\circ\text{C}80∘C for 15 minutes. Explain why.
Describe the role of micelles in the absorption of fatty acids into the cells lining the ileum.
