HUMAN ANATOMY PHYSIOLOGY Human Digestive System Animation Organs

HUMAN ANATOMY & PHYSIOLOGY

Human Digestive System Animation: Organs of Digestion

Warm-Up - journal Write down in correct sequence all the organs (at least 5) through which their food passes as it travels along the digestive tract. 2) Then try to list any glands or organs that are found along the digestive tract, but through which food does not pass. 1)

Following the Digestive Trail Accessory Organs Mouth Esophagus Tongue Epiglottis Pharynx (throat) Salivary glands Accessory Organs Stomach Small Intestine Large Intestine Pancreas Liver Gall Bladder

The Need for Digestion Major Functions: 1. Ingestion - taking in food 2. Digestion-ability to process food in the body into a form that can be absorbed and used or excreted. 3. Absorption -pulling nutrients out of the food, occurs in the small intestine 4. Egestion-removal of undigested food

Overview: Food processing occurs in four stages Small molecules Pieces of food Mechanical breakdown Nutrient molecules enter body Chemical breakdown (enzymatic hydrolysis) cells Undigested material Food 1 INGESTION 2 DIGESTION 3 ABSORPTION 4 ELIMINATION Figure 21. 2

A. Purpose q. Provides energy to stay alive q. Process of breaking food particles down into molecules small enough to be absorbed by cells food B. Why? n n To help build cells, tissues and O 2 organs ATP energy for synthesis ATP mitochondria

C. Types of digestion MECHANICAL q Changes the physical form of food (physical changes) – Mouth- teeth chew (masticate) & crush food – stomach muscles (rugae) grinds & churns 1. 2. CHEMICAL q Changes the chemical composition of food into a new substance with the aid of digestive enzymes ( chemical changes).

Review: Nutrition Food broken down to usable nutrients and absorbed into the bloodstream. – They are used by the body for metabolism, building and repair n Nutrients include carbohydrates, proteins, lipids, vitamins, minerals and water. n Carbohydrates – Broken down into monosaccharides – Body’s main source of energy. n Proteins – Broken down to amino acids – Supply the raw materials for growth and repair. n Lipids – Broken down to 3 fatty acids and glycerol – They are used to make steroid hormones, cell membranes – Store energy n

Nutrient End product (building blocks) Carbohydrate Simple sugars (glucose & fructose) Proteins Amino Acids Lipids (Fats) 3 Fatty Acids 1 glycerol Draw/label this IN: Nutrients & O 2 Diffusion (w/out energy & high to low) Diffusion & Active transport (with energy, low to high) To the cells Artery OUT: CO 2 Transport

D. Gastro Intestinal Tract n How is the digestive system similar to a vacuole in a one celled organism? Reference: RB: pg 13 table 1 -1 1. One celled organism (ameoba, parameciu, euglena)- it is intracellular (vacuoles release digestive enzymes) 2. Humans- it is Extracellular (outside the cells then absorbed into the bloodstream)

Review: Which type of digestion (mechanical or chemical)? Chewing a saltine? 2) Saliva breaking the saltine down into molecules of glucose? 3) Your tongue breaking pieces of a hamburger apart? 4) Pepsin (an enzyme) in your stomach breaking the hamburger into amino acids? 1)

Digestion System video clip –click on image. Digestion biology Animation

Your Turn…learn the functions of the organs n Group Activity - match function card with the organs in your activity packet n As a Pair - Go to: My computer Assignments (drive R: ) KE Connelly Living Environment Digestion ppt n Return to seats and check your cards – rearrange if necessary to make it correct n Write the functions in your chart

Following the Digestive Trail – a one way tube Accessory Organs Mouth Esophagus Tongue Epiglottis Pharynx (throat) Salivary glands Accessory Organs Stomach Small Intestine Large Intestine Pancreas Liver Gall Bladder

Following the Trail 1 Mouth n Mechanical digestion begins here - chewing/crushing food n Salivary glands secrete saliva, which moistens and lubricates food for swallowing. n Saliva contains amylases (enzymes), which start the chemical breakdown of carbohydrates (starch). All that in spit!

Following the Trail 2 Esophagus Muscular tube (aka: food tube) n As we swallow, we push food along the tube until the food reaches our stomach. This process of pushing down the food uses muscular wave-like contractions is called peristalsis – Peristaltic contractions transport food to the stomach and allow a person to swallow even if he/she are upside down. – Peristalsis biology Animation n Click Here for animation

Following the Trail 3 Stomach n Food (bolus) mixes with acidic gastric juices (HCl) and an enzyme called pepsin to form chyme. n The chemical digestion of proteins begins in the stomach. q Mechanical digestion continues-stomach grinds & churns the bolus q https: //www. youtube. com/watch? v=h. Ba. E 22 s 64 IU But the stomach is made out of protein! What stops the stomach from digesting itself? mucus secreted by stomach cells protects stomach lining

Following the Trail 4 Small intestine Secretes digestive enzymes to begin breaking down fats • Continues and completes ALL chemical digestion of carbs, proteins and fats • Absorbs nutrients into the blood stream • S. I. lined with fingerlike projections, called villi, which, in turn, are covered by microvilli which increase surface area • The villi contain capillaries and lymphatic vessels for the absorption of nutrients • Nutrients move into blood stream by what process (Think H to L!)? DIFFUSION!!!!! • FYI- the small intestine has 3 parts:

A Closer look at the villi & microvilli of the small instestine n Absorption through increases surface area for absorption Cross-Section of small intestine SMALL INTESTINES 6 meters long, but can stretch to cover a tennis court Villi Microvilli

Following the Trail 4 cont…. the accessory (helper) organs n Food DOES NOT pass through these organs n These organs secrete substances to aid in digestion

Following the Trail 4 cont…. Pancreas Found under the stomach Secretes enzymes (lipase, amylase, protease) into the small intestine n Secretes a base into S. I. to neutralize stomach acid WHY? ? – So digestive enzymes aren’t denatured and can work! n Makes hormones insulin & glucagon to balance blood sugar levels to maintain homeostasis n pancreas small intestine

Homeostasis Balancing Blood Sugar levels insulin liver stores reduces body sugar appetite cells take up sugar from blood pancreas high liver blood sugar level low liver triggers releases sugar hunger liver pancreas glucagon Feedback

Following the Trail 4 cont…. Liver n Produces & secretes bile to emulsify (breaks up) fats Gall Bladder n stores bile & releases to the small intestine FYI - bile contains colors from old red blood cells collected in liver =iron in RBC rusts & makes feces brown

Following the Trail 5 Large intestines (colon) • • NO digestion occurs here WATER and vitamin K gets reabsorbed from undigested chyme • Lined with bacteria (E. coli) Rectum • Holds undigested or unabsorbed food wastes (feces) • mainly cellulose from plants called roughage or fiber- keeps everything moving & cleans out intestines • Masses of bacteria Anus • Final stop for undigested material…eliminate feces So don’t forget to wash your hands!

E. Digestive Homeostasis Disorders Body Invaders: Digestive Problems : Video : Discovery Health 1. Stomach 1) Mucus that prevents stomach from digesting itself a) Peptic ulcer occurs when layer of mucus fails (open sores) b) Gastric juices reach wall of stomach and begin to break down (painful) Ulcers biology Animation 2) Treatment Before: Antacid would reduce amount of acid in stomach but would return n Recently: Ulcer is an infection by acid resistant bacteria Helicobacter pylori n Treatment – antibiotics n

2. Appendix q No function – may have once been used to digest plants (vestigal organ) q Appendicitis – inflammation of the appendix – caused by E. Coli bacteria

3. Large Intestine n Constipation- too much water reabsorbed from the feces n Diarrhea-too little water reabsorbed from the of feces; prolonged diarrhea can cause dehydration of body tissues.

4. Colon Cancer n One of the most common types of cancers in North America n Colon – section before the rectum on lg. Intestine n Cause: – Diet low in fiber causes feces to move too slow through colon – Hereditary predisposition – https: //www. youtube. com/watch? v=h. RC 37 QTi. Zg 8 – https: //www. youtube. com/watch? v=Qoky. QOft. WGQ

5. Gallstones n small hard stones made of cholesterol that collect in the gallbladder. n Due to a high saturated fat diet n hereditary n Heart Burn Heartburn biology Animation

Digestive System Fill-In

Digestive System Fill-In Answers