Digestion text p.18 Structure of digestive system and its glands Large molecules are hydrolysed by enzymes to smaller molecules which can be absorbed and assimilated

Digestion demonstration Set up visking tubing demo

Mouth Salivary glands OesophagusStomachSmall intestine (duodenum + ileum) LiverColonRectumAnusPancreas (in loop of duodenum)

The Mammalian Digestive System The major accessory structures are: The salivary glands The liver The gall bladder The pancreas

Position of liverGall bladderDuodenumIleum (simplified)Position of pancreasAppendixCaecum

OesophagusStomachPancreas in loop of duodenum and behind the stomach Duodenum Gall bladder Position of liver Common bile and pancreatic duct opening entering the duodenum The liver manufactures bile and stores it in the gall bladder The pancreas is a mixed gland with both exocrine (digestive) and endocrine (insulin and glucagon) functions

Text p. 18/ diagram race Label your diagram with the following; Oesophagus, stomach, small and large intestine, rectum, salivary glands, pancreas You will need to learn these labels!!

The digestive system Show and tell model gut rectum 3 pairs salivary glands

Annotation Next to each label write the features functions of each part in a bullet list. You could colour code notes below with diagram parts if you wish

Small intestine

What is digestion? Physical digestion 1.Where does physical digestion take place? 2.What is the result of physical digestion? 3.Why is physical digestion not sufficient on its own? Chemical digestion 1.What is hydrolysis? 2.What carries out hydrolysis in the gut? 3.List the names of the enzyme groups and what they each do. 4.What is absorption? 5.What is assimilation? Extension 1.Which type of digestion is shown by the demonstration? 2.Try to design a model to show how each of the hydrolase enzymes work based on what you remember from GCSE. Use pictures/play doh/ card/poster etc.

Digestive Enzymes Digestive enzymes catalyse the hydrolysis of many different food molecules and are manufactured in various regions of the digestive system Carbohydrases catalyse the hydrolysis of starch (polysaccharide) and disaccharides Proteases catalyse the hydrolysis of proteins and peptides Lipases catalyse the hydrolysis of triglycerides (fats and oils) These enzymes are manufactured by glands and act either extracellularly (within the cavity of the gut) or intracellularly (within the membranes of epithelial cells that line the alimentary canal)

Sources and Locations of Digestive Enzymes Mouth – salivary glands manufacture and secrete carbohydrase into the oral cavity Stomach – gastric glands manufacture and secrete proteases into the stomach cavity Intestine – the pancreas secretes carbohydrases, proteases and lipases into the lumen of the duodenum Intestine – intestinal glands manufacture various enzymes, many of which function as brush-border enzymes Digestive glands secrete specific enzymes that function in different regions of the digestive tract

Summary of digestive enzymes Nutrientenzymeproduct carbohydratescarbohydraseMonosaccharides (single sugars) ProteinproteaseAmino acids FatlipaseFatty acids and glycerol

Digestion demo Results for visking tubing demo

Homework Text p.19 q 1-4 Text p.20 q 1-3

Digestion text p.18 Structure of … and its … … are … by … to … which can be … and … Digestive system bounce quiz on echalk