Transcript Alimentary Canal - World of Teaching
The Alimentary Canal Standard Grade Biology Can you sort out the statements into True and False? Carbohydrates, proteins and fats are all made up of carbon, hydrogen, nitrogen and oxygen. Fats are made up of smaller units called amino acids Starch is a large carbohydrate molecule Proteins are made up of one or more glucose molecules Proteins are important for the growth and repair of cells Starch molecules can be broken down by amylase. Can you name the 2 different ways we breakdown food in our bodies? 1. Mechanical Digestion -teeth 2. Chemical Digestion -enzymes -bile -stomach acid 1. Parts of The Alimentary Canal The alimentary canal (or gut) is the tube within the body through which food passes and is processed in various ways mouth salivary glands oesophagus liver stomach pancreas large intestine small intestine anus 2. Role of the Mouth Teeth assist the mechanical breakdown of food Saliva is mixed with food during chewing Saliva contains the enzyme amylase which starts the digestion of food Salivary gland Salivary gland Salivary gland Saliva contains mucus that keeps the mouth moist and lubricates food for easier swallowing 3. Muscles of the Alimentary Canal • Food has to be kept moving along the alimentary canal whilst being mixed with various juices • These actions are brought about by muscles in the walls of the canal over which a person has little or no conscious control 3. Peristalsis The squeezing action of muscles that is used to move food along the alimentary canal http://www.lionden.com/peristalsis.htm Digestive Enzymes • What do the following enzymes breakdown? • What do they break the large moleculs down into? • Amlyases • Lipases • Proteases Digestion ‘the breakdown of large insoluble molecules into soluble molecules’ Digestion and Digestive Juices Saliva GASTRIC JUICE Bile PANCREATIC JUICE INTESTINAL JUICE Sites of production of main digestive juices Site of digestive juice production Mouth Main digestive juice produced Saliva Stomach Gastric juice Liver Pancreas Bile (breaks down big fat droplets into little fat droplets Pancreatic juice Small Intestine Intestinal juice Digestion and Digestive Juices SALIVA •Salivary amylase GASTRIC JUICE Bile •Hydrochloric acid •Pepsin (protease) PANCREATIC JUICE INTESTINAL JUICE •Pancreatic lipase In the Mouth… Salivary amylase Starch maltose • Broken down into glucose later by other amylases In the stomach pepsin Protein peptides Broken down into amino acids later by other proteases In the pancreas…. Pancreatic lipase Fats fatty acids and glycerol After all the digestive enzymes have done their work… • Glucose • Amino acids • Fatty acids • Glycerol Finish the sentence…. • Something new I learnt today was….. • Something I found difficult to understand was… • The thing I need to revise from today’s lesson is… This powerpoint was kindly donated to www.worldofteaching.com http://www.worldofteaching.com is home to over a thousand powerpoints submitted by teachers. This is a completely free site and requires no registration. Please visit and I hope it will help in your teaching.