Digestive System 0.0 / 5 ? BiologyEnzymes and digestionGCSECCEA Created by: PhoenixStormCreated on: 05-06-18 10:52 Buccal cavity Mechanical digestion increases the surface area of food Amylase in saliva digests starch 1 of 7 Oesophagus A bolus (food ball) is squeezed down by wavelike contractions of surrounding muscle called peristalsis 2 of 7 Stomach Mechanical digestion caused by the physical churning of the muscular wall Chemical digestion caused by pepsin digesting proteins Hydrochloric acid in gastric juices kills microbes 3 of 7 Duodenum The main site of digestion Food is mixed with intestinal juice and pancreatic juice containing enzymes Contains bile which is: Produced by the liver Stored in the gall bladder Alkaline Able to digest fats Not an enzyme Bile breaks large droplets of fats into small droplets increasing the surface area; this is calle emulsification 4 of 7 Ileum Responsible for absorption of digested food across the gut wall Surface area is increased as it is long and has folded walls and villi In villi: The lacteal carries fatty acids and glycerol The venule carries amino acids and simple sugars The network of capillaries give them a good blood supply 5 of 7 Colon Responsible for reabsorption of water 6 of 7 Rectum and anus For storage and removal of faeces 7 of 7
Comments
No comments have yet been made