Aqa A Level Biology: Digestion & Absorption From Ingestion T

AQA A LEVEL BIOLOGY: DIGESTION & ABSORPTION - FROM INGESTION TO ASSIMILATION MASTERY! AQA A Level Biology: Digestion and Absorption What is hydrolysis? Breaking bonds by adding water What is digestion Physical breakdown Chemical digestion Physical breakdown -Breakdown of food into absorbable nutrients - By teeth - Stomach muscles - increases SA Chemical digestion Hydrolyses large, insoluble molecules What is the importance of digestion?Hydrolyses large food molecules into smaller molecules Which can move across cell membrane And be absorbed into the blood Oesphagus carries food from mouth to stomach. adapted for transport. made up of a thick muscular wall stomach muscular sac between the oesphagus and the small intestine where digestion of food begins produces enzymes ileum Part of small intestine Long muscular tube Enzymes from walls and glands digest food Inner walls folded for large SA (have microvilli) large intestine Absorbs water and forms feces Rectum stores feces Salivary glands Contain amylase to hyrdolyse starch into maltose PancreasPancreatic juice (hydrolyse proteins, lipids and starch) Why are different enzymes needed to catalyse the breakdown of carbohydrates, proteins and lipids? Enzymes are proteins with specific tertiary structures Active site complementary to a specific substrate Only specific substrate will bind to active