Describe the differences between the process of facilitated diffusion and the process of active transport across cell membranes.
State the function of the high density of mitochondria found within the epithelial cells lining the ileum.
Vitamin A is a lipid-soluble nutrient. Micelles are required for its efficient absorption. Describe the role of micelles in the absorption of Vitamin A into the epithelial cells of the ileum.
12 exam-style questions on AQA A Level Biology Digestion and absorption, covering Digestion and absorption. Each one has a worked solution and a mark scheme showing where the marks go.