Digestive System All living things maintain Homeostasis Objectives

Digestive System All living things maintain Homeostasis.

Objectives for the Week of 11/9 • Identify and describe the function of the major organs of the digestive system • Construct a model to illustrate the path of digestion • Differentiate between mechanical and chemical breakdown • Explain the difference between breakdown and absorption of nutrients

Digestion is…. • Breaking nutrients into smaller pieces to make it easier for the body to absorb – Cells will use nutrients to perform functions • Importance: • Allows organism to obtain vital nutrients for health and survival

Digestion • Chemical digestion – the use of chemicals to break bonds *Enzymes: chemicals that speed up reactions * Acid: break down/dissolve • Mechanical digestion – the use of physical force to break food into small pieces and increase surface area • Ripping, Cutting, Tearing, Churning, Peristalsis • Absorption – nutrients entering the cells of the body for use Chemical Digestion Mechanical Digestion Absorption

Nutrition • • Water Vitamins Minerals Biomolecules – Carbohydrates – Lipids/Fats – Proteins

Mouth • Type of digestion: • Mechanical: • Teeth – break food into pieces to increase surface area • Chemical: • Amylase= carb/starch enzyme in saliva • Special information: • Food forms a ball called a “bolus”

Esophagus- “food tube” • Type of digestion: • Mechanical: • peristalsis = wave of contraction to move food • Chemical: NONE • Special information: • muscular tube transports food to stomach

• Type of digestion: • Mechanical: • Churning Stomach • Chemical: Pepsin – enzyme for protein HCl Acid – weakens chemical bonds *Mucus- protects lining Special Information: Food forms a liquid called “chyme”

Small Intestine: 21 feet long • Type of Digestion: • Mechanical: • peristalsis • Chemical: • from Pancreas, Gallbladder and Liver • Bile [fats], Lipase [fats], Amylase [carbs] Protease [proteins] • Special Information: • Absorption: – nutrients enter the cells by the bloodstream

Large Intestine: 5 feet long • Type of digestion: • Mechanical: • Peristalsis • Chemical: none • Special Information: • Absorption- water

Accessory Organs & Glands [food does NOT pass through] • • Salivary glands Liver Gallbladder Pancreas

Salivary Glands • Function: produce saliva to lubricate and begin breaking down food • Chemical: AMYLASE-Enzyme that breaks down starch

Liver- largest internal organ • Functions: • Storage – Carbohydrates • Detoxification – Removes harmful substances • Alcohol, medications • Chemicals: – Produces Bile for Fats – enzymes

Gallbladder- green sac under the liver • Function: • Stores Bile • Chemicals: • BILE for fat breakdown

Pancreas-gland near stomach • Function: • Produces chemicals that digest proteins, carbohydrates, fats • Chemicals: • Lipase, Protease, Amylase • Insulin- regulates Blood sugar • Sodium Bicarbonate (baking soda) – neutralizes stomach acid

Digestion Animation • Check out all the different types of food and what happens to them • http: //kitses. com/animation/swfs/digestion. s wf