INTRODUCTION Grade 11 Human Nutrition for 2013 Flipped classroom?
Flipped Classroom advantages…
What I want you to do? Make your own life sized poster on the Human Digestive System: Journey of BIG MACromolecules to Smaller molecules. 4 Parts to this journey (make sure you have the 4 hand outs and mark schemes) 1. Structure and Function (Group) 2. Digestive Processes (Group) 3. Chemistry of Life (Extension work for group) 4. Digestive Processes (Individual) Textbook: Shuters Top Class Life Sciences, Grade 11 (2012).
Lets get the show on the road! Read over all the instructions first! Make sure youve read and understood the mark scheme.
Animal Nutrition Food gives organisms energy for all cellular functions. Producers/autotrophs Consumers/heterotrophs: Herbivores Carnivores Omnivores
Part 1: Structure and Function Overview Eyes, Nose and tongue Mouth and teeth Oesophagus Stomach Small Intestine (duodenum, jejunum and ileum) Colon/Large Intestine Rectum and anus Salivary glands Liver and gall bladder Pancreas Click movie icon to start Introd uction to Digest ion Video !
Sensing food and the mouth, tongue and teeth All starts with the senses in the body! Mouth: Beginning of the Big Macs journey Tongue and teeth inside the mouth Tongue tastes food and helps you swallow Teeth break up food into smaller pieces = mechanical digestion/mastication 3 pairs of salivary glands that produce saliva: Water, slippery mucin and enzymes (lysozyme and salivary amylase) Helps to form bolus and lubricate it for swallowing Sense of taste and smell video Teet h vide o
Structure: Teeth 4 types: Incisors canines premolars Molars Humans 2:1:2:3 Textbook Pg 123 & 131 Q 1: Which set of teeth belongs to which type of consume r and give reasons why?
Passed the pharynx, through the oesophagus Pharynx (throat): Muscular part at the back of mouth Opens to trachea (to the lungs) and oesophagus (to the stomach) Oesophagus: Narrow muscular tube Bolus moves down through contraction and relaxation of muscles in process called = PERISTALSIS Q 2: Can you think of other example s in the body where perista lsis is used to move things? Textbook Pg 133
Into the stomach Large bag that receives and holds food. At each end of the stomach there are valves called sphincters that control the movement of food; Cardiac sphincter at the top end pyloric sphincter at the bottom end Cells lining the stomach secrete gastric juice. Hydrochloric acid (HCl), low pH Mucus, high pH Proteases, (pepsinogen) Alcohol, Vit B 12 and aspirin are absorbed. Food leaves the stomach as chyme. Stom ach vide o
Into the not so… small intestine Soupy chyme enters small intestine. Folded tube (5 -7m long) Lined with columnar epithelial cells 3 parts: Duodenum Jejunum Ileum Duodenum has Brunners glands which secrete alkaline rich mucus; Neutralise Chyme Provide right pH for enzymes Lubrication Digestion of food is completed so that simple soluble nutrients can be absorbed. Carbohydrates, fats and proteins are digested Most digested food absorbed Smal l inte stin e vide o
Large intestine Large intestine/colon stretches like a frame around the small intestine. Main functions: Absorb water, dissolved minerals and vitamins Helped by over 700 species of bacteria (gut flora) Caecum and appendix are two structures where small intestine joins large intestine; No digestive function but contain tissue from the immune system Very large in organisms that digest cellulose Rectum is short tube at end of large intestine; Stores indigestible remains for short time before being expelled At the opening end of rectum is anus; Surrounded by sphincter muscles to help control movement of faeces Larg e inte stin e vide o
Associated glands: Salivary Glands and Pancreas 3 salivary glands that secrete saliva. Pancreas that secretes pancreatic juice. Travels down duct into duodenum (exocrine gland) Contains enzymes for breaking down food Carbohydrases: starch maltose Proteases: proteins amino acids Lipases: lipids fatty acids and glycerol Contains alkaline salts for neutralising acidic chyme Pancreas controls blood sugar levels by secreting hormones insulin and glucagon (endocrine gland).
Associated glands: Liver Largest gland and solid organ in the body. Liver has many functions: Secretes bile which is stored in gall bladder. Bile neutralises acidic chyme Emulsifies fats into small droplets Controls release of glucose in blood by converting glucose glycogen. Controls excessive amino acid concentrations in the body through deamination. Process where amine group is removed from amino acid producing a carbohydrate and urea. Transports both glucose and amino acids if necessary via hepatic vein (vessel from liver to heart) to the heart and then to cells of the body. Store vitamins and minerals (if not needed pass out through urine). Alcohol and drugs are transported via hepatic portal vein (vessel from small intestine or stomach to the liver) to be metabolised. Liv er fac t pac k
Get on with Part 1…
Part 1: Structure and Function Textbook page 125
Other possible human nutrition tasks Food diary - nesspal.com/ nesspal.com/ Analyse nutritional information packaging Dietary supplements for sport analysis
Cultural and socio-economic influences on diet Italy : The Manzo family of Sicily R 1976 per week
Germany : The Melander family of Bargteheid e R 3712 per week
United States : The Revis family of North Carolina. R 2538 per week
Mexico : The Casales family of Cuernavaca R 1403 per week
Poland : The Sobczynscy family of Konstancin - Jeziorna R 1123 per week
Egypt : The Ahmed family of Cairo R 507 per week
Ecuador : The Ayme family of Tingo R 234 per week
Bhutan : The Namgay family of Shingkhey Village R 37 per week
Chad : The Aboubakar family of Breidjing Camp R 9.13 per week