The Digestive System – Part 1 Gaiser Life Science

Know What are the functions of the digestive system? (There are three of them.) Evidence Page 61 The Digestive System – Part 1 I dont know any. is not an acceptable answer. Use complete sentences. After listening to the PowerPoint lecture, come back here and list evidence to explain why your answer to the above question is or is not a good answer. You may also use other outside sources to help you respond.

Clarifying ?s Information Page 62 functions 3. Wastes are eliminated from the body. 1. Break down food into molecules that the body can use. 2. Molecules are absorbed into the blood and carried throughout the body. - The process of the body breaking down food into small nutrient molecules 2. Chemical – Enzymes produced by the body are used to break food down to its smallest components. Example: When you take a bite of food, teeth break it apart and grind it while saliva makes the food moist. Two kinds of digestion 1. Mechanical – Food is physically broken down into smaller pieces digestion The Digestive System – Part 1 Example: The starches in bread and potatoes are broken down into sugar molecules.

Clarifying ?s Information Page Food enters mouth and teeth and jaws cut and grind it for swallowing. (mechanical) The process of digestion FYI: Sugars end in –OSE – dextrose, lactose, maltose, etc. The matching enzymes that break them down usually end in –ASE – dextrase, lactase, maltase, etc. 2. Saliva coats food – 2 functions: 1. lubrication for easy swallowing, 2. Enzymes in saliva begin breaking down food. (chemical) - a protein that speeds up a chemical reaction. Each enzyme has a specific job Example: A starch enzyme cannot break down a protein. enzyme The Digestive System – Part 1

Clarifying ?s Information Page 64 Summary: The Digestive System – Part 1 3. Food is swallowed. (mechanical) Epiglottis blocks route to lungs – prevents gagging and breathing obstructions. 4. ring-like muscles in esophagus contract, which pushes food toward stomach. This is called peristalsis and only works in one direction. (mechanical) 5. Food enters stomach where food is squeezed, churned, and mixed. (mechanical) 6. Food mixes with mild hydrochloric acid in the stomach, which continues breaking down food. (chemical) 7. Food leaves the stomach as a thick liquid.

Clarifying ?s Information The Digestive System – Part 1 functions 3. Wastes are eliminated from the body. 1. Break down food into molecules that the body can use. 2. Molecules are absorbed into the blood and carried throughout the body. - The process of the body breaking down food into small nutrient molecules 2. Chemical – Enzymes produced by the body are used to break food down to its smallest components. Example: When you take a bite of food, teeth break it apart and grind it while saliva makes the food moist. Two kinds of digestion 1. Mechanical – Food is physically broken down into smaller pieces digestion Example: The starches in bread and potatoes are broken down into sugar molecules. FYI: Sugars end in –OSE – dextrose, lactose, maltose, etc. The matching enzymes that break them down usually end in –ASE – dextrase, lactase, maltase, etc. - a protein that speeds up a chemical reaction. Each enzyme has a specific job Example: A starch enzyme cannot break down a protein. enzyme

Clarifying ?s Information Summary: The Digestive System – Part 1 1. Food enters mouth and teeth and jaws cut and grind it for swallowing. (mechanical) The process of digestion 2. Saliva coats food – 2 functions: 1. lubrication for easy swallowing, 2. Enzymes in saliva begin breaking down food. (chemical) 3. Food is swallowed. (mechanical) Epiglottis blocks route to lungs – prevents gagging and breathing obstructions. 4. ring-like muscles in esophagus contract, which pushes food toward stomach. This is called peristalsis and only works in one direction. (mechanical) 5. Food enters stomach where food is squeezed, churned, and mixed. (mechanical) 6. Food mixes with mild hydrochloric acid in the stomach, which continues breaking down food. (chemical) 7. Food leaves the stomach as a thick liquid.

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