Slideshow covers the AQA AS Biology topic for Section 3.3.3: Digestion and Absorption. It breaks down how large biological molecules are broken down and absorbed by the body.

What is Covered:

• The Process of Digestion: The step-by-step hydrolysis of carbohydrates, lipids, and proteins, including roles of amylases, membrane-bound disaccharidases, lipases, bile salts, endopeptidases, exopeptidases, and dipeptidases.
• Mechanisms of Absorption: How digested nutrients move across the cell membranes of the ileum, focusing on sodium-glucose co-transport and the role of micelles in lipid absorption.
• Required Practical Skills: A guide to designing and interpreting experiments on enzyme reaction rates (such as the effects of pH and bile salts) and using Visking tubing as a model for the gut wall.
• Exam Practice: Includes exam-style questions and answers at the end to help test your understanding and practice applying the content to real assessments.