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Digestion and absorption
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Why digestion is necessary

Why digestion is necessary

Cross-section of ileum lining with villi, microvilli, capillary network and lacteal labelled Digestion is the hydrolysis of large, insoluble food molecules into small, soluble molecules. Because starch, proteins and lipids are too large or too hydrophobic to cross membranes directly, they must be broken down in the lumen of the alimentary canal.

Digestion and absorption Lesson

  1. A Level
  2. /Biology
  3. /Digestion and absorption

Step-by-step lessons covering AQA A Level Biology Digestion and absorption for A Level Biology. Each lesson breaks down Digestion and absorption, then works through exam-style questions in Paper 1, Paper 2 and Paper 3 format. Build a strong foundation in cell biology and biochemistry early on, since later topics on genetics, ecology and physiology all draw on these core concepts.