169 Digestive System Notes and Ws 2/17/15 Starter: Digestive System Notes and Ws170 2/17/15 Application/Connection: Digestive System Ws Tu Practice: Glue notes here Exit: Explain what happens in the mouth when you chew food. The iron aorta Vena cava Ventricle plasma Platelets tissues cells hemoglobin organs marrow vertebrae cranium Cartilage Joints sternum component of blood February 17, 2015 AGENDA Objective 7.12 B Identify the main functions of the systems of the human organism, including the circulatory, respiratory, skeletal, muscular, digestive, excretory, reproductive, integumentary, nervous, and endocrine systems by completing a skeletal system worksheet 1. Starter 2. Digestive System Notes 3. Digestive System Ws Table of Contents Date Lecture/ Activity/ Lab Page 1/27 Cell State 1/28 Cell Comparison Booklet 1/29 Mitosis Notes 1/30 Mitosis Poster 2/2 Mitosis Sort and Review 2/3 Test Review 2/5-6 Body Systems Overview 2/9 Skeletal and Muscular system notes 2/10-11 Skeletal System Activity 2/12 Muscular System Ws 2/13-16 Muscular System Lab 2/17 Digestive System Notes and Ws 147-148 149-150 151-152 153-154 155-156 157-158 159-160 161-162 163-164 165-166 167-168 169-17 The Digestive System and Nutrition Important Vocabulary • Digestion: The process of breaking food down to be used by the body. – Why is digestion important? • Food must be broken down in order for our body to be able to absorb all of the substances important for daily functions. • Food must small enough to be absorbed into the blood and carried to the cells. Important Vocabulary • Digestion cont: – Two types of digestion: • Mechanical Digestion: occurs in the mouth (chewing), and in the stomach (churning of stomach muscles) • Chemical Digestion: occurs through the use of enzymes (substances which chemically act on food to break it down) in saliva, the stomach, in the small intestine Important Vocabulary: Organs of the Digestive System • Mouth: The first step in digestion is actually getting the food into your body. – Teeth: mechanically break food down into smaller pieces – Saliva: softens food and chemically breaks food down further – Tongue: moves food around the mouth, forms a bolus (ball of food) Important Vocabulary: Organs of the Digestive System • Esophagus: a hollow tube at the back of the throat that connects to the stomach. – To prevent food from “going down the wrong pipe” a flap of skin called the epiglottis closes over the opening of the trachea (windpipe) when we swallow – Peristalsis: muscular contractions that move food down the esophagus into the stomach. • Imagine squeezing a tube of toothpaste… Important Vocabulary: Organs of the Digestive System • Stomach: a hollow, J-shaped organ located below the esophagus and above the small intestine. – The stomach uses both mechanical and chemical digestion to break food particles down. • Mechanical digestion: 3 layers of muscles • Chemical digestion: digestive or gastric enzymes Important Vocabulary: Organs of the Digestive System • Small Intestine: responsible for absorbing nutrients from food. – First 1/3 of the S.I. :Bile from the gall bladder and digestive enzymes from the pancreas and walls of the small intestine further break food down. – Second 1/3 of the S.I.: contains fingerlike projections called villi Important Vocabulary: Organs of the Digestive System • Small Intestine cont: – Villi: increase the surface area of the S.I. so that more nutrients can be absorbed into the blood stream Important Vocabulary: Organs of the Digestive System • Large intestine: “large” because it is wider in diameter than the small intestine (about 3” vs. 1”). Responsible for absorbing water from undigested food. – Material found in the large intestine is mostly food that cannot be digested any further and water. Important Vocabulary: Organs of the Digestive System • Large Intestine: 3 parts – Colon: Absorbs water and nutrients from food, as the material moves through the colon it gets harder and harder-turning into feces. – Rectum: Stores feces. Feces move to the anus by peristalsis. – Anus: Eliminates solid waste from the – body Other Organs • Liver: produces bile, is located to the right of the stomach. – Bile: responsible for breaking down fats • Pancreas: located behind the stomach, and above the small intestine. – Secretes digestive enzymes Gall Bladder: stores and excretes bile 169 Digestive System Notes and Ws 2/17/15 Starter: Digestive System Notes and Ws170 2/17/15 Application/Connection: Digestive System Ws Tu Practice: Glue notes here Exit: Explain happens in the mouth when you chew food.