Animal Nutrition (The Digestive System) Past Paper PDF

[email protected] Animal Nutrition (The Digestive System) Ms. Cunningham Name: ________________________________.ie Subtopics Covered In This Chapter: Types of Nutrition ge...

[email protected] Animal Nutrition (The Digestive System) Ms. Cunningham Name: ________________________________.ie Subtopics Covered In This Chapter: Types of Nutrition ge Events in Human Nutrition le The Digestive System ol Mouth Oesophagus ac Stomach dr Pancreas, Liver & Bile an Small Intestine Large Intestine ex Balanced Diet al Look at the Past Exam Q’s Booklet for All Past Exam Paper Questions @ Memory Tips For This Topic: m ha ng ni un Past Exam Paper Questions Found Difficult ac ar ci Other Helpful Resources (YouTube Videos, Handouts Etc.) [email protected]  [email protected] TYPES OF NUTRITION: NUTRITION is the way in which an organism GETS and USES its food MEMORY TIP: Auto - Automatically Happens - The Organisms Make Their OWN Food “Automatically”.ie AUTOTROPHIC means that an organism makes its own food ge E.G. Plants and some bacteria are autotrophs le ol HETEROTROPHIC means that an organism takes in food from its environment ac E.G. Animals, Fungi and some bacteria are heterotrophs dr an There are THREE TYPES of heterotrophs 1) HERBIVORES are animals that feed ONLY on plants E.G. Cattle & Rabbits ex 2) CARNIVORES are animals that feed on OTHER animals E.G. Dogs & Cats al @ 3) OMNIVORES are animals that feed on plants AND animals E.G. Badger & Foxes m EVENTS IN HUMAN NUTRITION ha INGESTION Is the taking in of food into the MOUTH (DO NOT SAY body) ng DIGESTION Is the PHYSICAL and CHEMICAL breakdown of food. ni ABSORPTION Occurs when food passes from the small intestine into the blood or lymph systems un EGESTION Occurs when unabsorbed waste passes out through the anus ac ar WHY IS DIGESTION NECESSARY ? ci Digestion is necessary to allow small molecules of food to be absorbed through the walls of the intestines MECHANICAL DIGESTION: Food is physically digested by the teeth, by the churning of the stomach and by the action of bile CHEMICAL DIGESTION: Food is chemically digested by enzymes [email protected]  [email protected] THE DIGESTIVE SYSTEM( ALSO CALLED THE ALIMENTARY CANAL):.ie ge le ol ac dr an ex al @ m ha ng ni MOUTH: un Mechanical Digestion is carried out by the teeth. There are four types of teeth. ac ar ci [email protected]  [email protected] TYPES OF TEETH IN HUMAN MOUTH: A) INCISORS are at the front and have sharp They are used to CUT and M.T. They are the 1st chiselled edges SLICE food teeth INside our mouth B) CANINES Are long pointed, FANG-LIKE They GRIP and TEAR food M.T. K9 = Dog teeth The Canines look like Dog’s teeth C) PREMOLARS Are larger teeth than the incisors They are used to chew, M.T. Pre = Before and canines crush and grind food These teeth are before.ie the molars D) MOLARS Are largest of the teeth They are used to chew, M.T. Molar sounds like ge crush and grind food Mammoth Molar=Mammoth = Large le ol THE HUMAN DENTAL FORMULA ac This dental formula tells us the number of each type of tooth on 1 side of the human mouth. dr anTHE HUMAN DENTAL FORMULA FOR AN ADULT: ex al @ m ha A child has the same formula but does NOT have molar teeth i.e. total amount of teeth = 20 ng CHEMICAL DIGESTION: ni CHEMICAL DIGESTION: is carried out by the enzyme amylase. un ac Amylase is contained in saliva. Saliva is produced in the salivary glands. The pH of the mouth is between 7 and 8. This pH allows amylase to work. ar ci Amylase digests starch to maltose [email protected]  [email protected] TABLE OF SUMMARY FOR ENZYMES: ENZYME MADE pH SUBSTRATE PRODUCT Pepsin Stomach Lining 2 Protein Peptide Amylase Salivary Glands /Pancreas 7-8 Starch Maltose Lipase Pancreas 7-8 Fat Fatty Acids and Glycerol.ie OESOPHAGUS: The oesophagus, along with the rest of the alimentary canal, is made of involuntary ge muscle. le Regular contractions of this muscle push food along the alimentary canal. This ol process is called PERISTALSIS ac Peristalsis forces food through the oesophagus to the stomach. dr an Fibre (or roughage) is essential in the diet in order to STIMULATE peristalsis ex al @ m ha ng ni un ac ar STOMACH: ci The stomach is a muscular bag in which food remains for 2-4 hours MECHANICAL DIGESTION: occurs when the stomach churns the food. Churning helps to turn the food into a liquid called CHYME CHEMICAL DIGESTION: occurs due to the action of a number of enzymes [email protected]  [email protected] PEPSINOGEN is an active enzyme that is formed by glands in the lining of the stomach. It is activated to form pepsin in the stomach by hydrochloric acid Different glands in the lining of the stomach produces this acid that causes the pH of the stomach to be highly acidic (about pH 2) PROTEASE = is a protein-digesting enzyme PEPSIN digests proteins to peptides..ie ge le ol ac dr The stomach is prevented from being digested by pepsin and acid because an A) It is lined with a protective mucous ex B) Pepsin only becomes active when it mixes with acid in the stomach al WHERE DO THE PRODUCTS OF THE LIVER AND THE PANCREAS ENTER? @ The products of the liver and pancreas enter the duodenum m ha ng ni un ac ar ci [email protected]  [email protected] PANCREAS: The pancreas produces the hormone insulin and enzymes such as amylase and lipase Pancreatic amylase has the same function as salivary amylase. It is produced to replace the salivary amylase that was destroyed (denatured) by the acid in the stomach Lipase digests fats to form fatty acids and glycerol.ie ge le ol ac dr an LIVER: ex The liver is the only organ that gets its blood from two major vessels 1) The Hepatic Artery al 2) The Hepatic Vein @ Blood leaves the liver in the hepatic vein m ha ng ni un ac ar ci [email protected]  [email protected] FUNCTIONS OF THE LIVER: Breaking Down Old Red Blood Cells Forming Bile Breaking Down Poisons (Detoxifying) Breaking Down Unwanted Amino Acids To Form Urea (Deamination) Converting Glucose To Glycogen Converting Excess Carbohydrates To Fat Storing Vitamins and Minerals Forming Plasma Proteins Such As Fibrinogen Forming Cholesterol (Used To Make Hormones) Producing Heat To Warm The Blood.ie Bile is composed of water, bile salts and bile pigments ge BILE is a yellow-green liquid formed from the breakdown le of red blood cells. ol ac BILE IS: Made in the Liver dr Stored in the Gallbladder Released into the Duodenum Through The Bile Duct an ex FUNCTIONS OF BILE IN THE DUODENUM: al @ To Emulsify Fats i.e. To Break Large Blobs of Fat Into Smaller Particles To Neutralise The Acid Coming From The Stomach m To Eliminate Bile Pigments From The Body ha SMALL INTESTINE: ng The small intestine’s diameter is small (approx 3cm) but the tube is very long (approx. 6m) ni The Duodenum: is the first 25cm of the small intestine. un Food is forced forwards and backwards through the duodenum by peristalsis. The lining of the duodenum by peristalsis. ac The lining of the duodenum produces a large range of enzymes. ar The function of the duodenum is digestion ci HOW FOOD LEAVING THE DUODENUM HAS BEEN DIGESTED: i.e. The Final Products of Digestion FOOD DIGESTED TO Carbohydrates Glucose Proteins Amino Acids Fats Fatty Acids and Glycerol [email protected]  [email protected] ILEUM: The Ileum is the second part of the small intestine. Its function is absorption The ileum has numerous infoldings called villi (plural), villus (singular) The villi increase the surface area for absorption The villi have numerous microvilli The lining of the villi is only one cell thick (i.e. very thin).ie ge le ol ac dr an ex al The Above is a Diagram of a Transverse Section of The Small Intestine (Ileum) @ m ha ng ni un ac ar ci The Above is a Longitudinal Section of The Small Intestine (Ileum) [email protected]  [email protected] FROM THE VILLI TO THE BLOODSTREAM: Glucose and amino acids pass from the villi into the bloodstream and are carried to the liver by the Hepatic Portal Vein Fatty acids and glycerol are enclosed in a covering and pass into lacteals. Each lacteal is located in the centre of a villus The lacteals contain a fluid called Lymph The fatty acids and glycerol are carried by the lymphatic system and pass into the bloodstream near the neck The coating is removed and the fats pass through the body cells.ie ge le ol ac dr an ex The Above Shows The Ileum (Small Intestine) and its Villi, Associated Lymph Vessel, Capillaries and Layers of Muscle al @ ADAPTATIONS OF THE SMALL INTESTINE: m ha It is made of muscle (ALLOWS PERISTALSIS, MOVES FOOD ALONG) The duodenum produces many enzymes (IMPROVES DIGESTION) ng It is very long (IMPROVES ABSORPTION) It contains villi and microvilli (IMPROVES ABSORPTION) ni The villi have thin walls (IMPROVES ABSORPTION) un There is a rich blood supply (TO TRANSPORT THE ABSORBED FOODS) Each villus contains a lacteal (TO ALLOW LIPIDS TO BE ABSORBED) ac ar LARGE INTESTINE: ci The large intestine is large in diameter (about 6cm) but is only 1.5m long. The large intestine is the broader term that includes several parts, one of which is the colon. The large intestine is the final part of the digestive system and consists of the cecum, colon, rectum, and anal canal [email protected]  [email protected] FUNCTIONS OF THE LARGE INTESTINE: Reabsorb Water Form Faeces Absorb Vitamins Made By Bacteria COLON: The colon is the largest section of the large intestine. Water is mainly reabsorbed in the colon. CAECUM AND APPENDIX:.ie The functions of the caecum and appendix are not fully understood ge le ol ac dr an ex Semi-solid waste (called FAECES) is stored in the rectum and EGESTED through the anus al @ SYMBIOTIC BACTERIA: m ha The large intestine contains a huge number of bacterial cells. ng These bacteria benefit us in two ways ni 1) Some of them produce some B group vitamins and vitamin K un 2) Other types of bacteria break down small amounts of cellulose ac Both of the types of bacteria are *symbiotic or *mutualistic ar ci *Symbiotic or *Mutualistic means that they live in close association with us and both humans and bacteria benefit [email protected]  [email protected] BALANCED DIET: A balanced diet contains the correct portions of the following seven components 1. Carbohydrates 2. Proteins 3. Fats 4. Vitamins 5. Minerals 6. Fibre 7. Water.ie ge FACTORS THAT INFLUENCE THE TOTAL AMOUNT OF FOOD REQUIRED BY A PERSON: le ol Age - Young, growing people need more food than older people ac Activity Levels - More active people like athletes require more food than people who are less active dr an Gender - Males require more food than female as males have greater muscle mass ex Health - People who are ill use and need less energy than those who are in good health al @ FOOD PYRAMID: m ha ng ni un ac ar ci [email protected]