Digestive system

1. Digestive system By: AleksaRomanowski, Kayla Lewis, Jordan Scott, Emmani Mays 2nd hour

2. The parts and functions of the digestive system • Teeth- digestion starts at the teeth. The job of the teeth is to crush the food into tiny pieces. • Saliva- saliva helps soften the food so it is easier to swallow. Saliva is also the first several chemicals that break down the food into simpler forms. • Tongue- The tongue works with the food and the saliva to form a “ball” that can be swallowed. • Esophagus- is a transportation tube from the mouth to the stomach. Food moves down the esophagus using muscles, not gravity. • Stomach- Once food gets into the stomach, the stomach uses chemicals to make the food tinier. The food is mixed with chemicals for about 3 hours. • Liver (Gall Bladder)- The liver makes a chemical called bile, which is stored in the gall bladder. When the gall bladder mixes bile with our food, it breaks down the food, and breaks down the fat, which supplies us energy. • Pancreas- adds a digestive chemical as the food leaves the stomach. This works on breaking down carbohydrates. • Small intestine- the small intestine contains blood vessels that can absorb tiny food molecules and send them to different parts of the body through our blood. • Large intestine- stores whatever the body cannot put in to use. Many plants for example, contains cellulose, which cannot be digested.

3. Mechanical and chemical digestion • Mechanical Digestion is the breaking of food into digestible chunks, normally using teeth • Chemical Digestion is the act or process of converting food into chemical substances that can be absorbed and assimilated.

4. what dietary component supplies most of the body’s energy? • The components of food are certain organic substances and minerals found in food called nutrients. They provide the body with energy and enable it to grow, repair and maintain itself. • Sphincter allows food to enter the stomach then squeezes shut to keep the food or fluid from coming back up into the esophagus. • Stomach muscles grinds and mixes the food with acids and enzymes into digestible pieces. • Most substances in food need further digestion and has to travel into the intestine before being absorbed.

5. What is the importance of the liver and pancreas in digestion? • Your liver secretes bile into your small intestine. This bile contains worn out red blood cells that must be removed from the body. • The pancreas also secretes insulin, which helps remove glucose (blood sugar) from blood into cells. Diabetes is a common and very serious disease that results from lack of insulin.

6. Bile • Bile plays a role in the digestion of fats. Most present in mammals. The bile is formed in the liver and composed of cholesterol, lecithin, pigments, and salts.

7. Hormones • Hormones in the body regulate how the body uses chemicals and different minerals in the body. The hormones help the body maintain homeostasis by making sure everything is running smoothly and working together.

8. Function of pharynx • Pharynx is divided into three regions. The regions are nasopharynx, oropharynx, and larynogpharynx. Air passes from the nose through the nasopharynx, while both food and the air passes from the mouth into the oropharynx, the next passage of air goes through the lungs which is called laryhgopharynx.

9. What is peristalsis? • A sequence of muscle contractions that progressively squeeze one small section of the digestive tract and then the next to push food along the tract, something like pushing toothpaste put of its tube

10. Where is the urea formed? The uera forms in the liver from amino acids and from compounds of ammonia.

11. Function of Duodenum • Duodenum is the first section of the small intestine and when digestion is completed it releases nutrients through the capillary walls into the blood stream, which carries them into all parts of the body.

12. What are the functions of the villi in the small intestine? • Villi is a finger like projection that covers the surface lining of the small intestine. Nutrients is absorbed through the surface of diffusion and active transport.

13. One disorder of the digestive system • Gastroesophageal reflux disease (GERD) is a more serious form of gastroesophageal reflux (GER), which is common. GER occurs when the lower esophageal sphincter (LES) opens spontaneously, for varying periods of time, or does not close properly and stomach contents rise up into the esophagus. GER is also called acid reflux or acid regurgitation, because digestive juices—called acids—rise up with the food. • The main symptom of GERD in adults is frequent heartburn, also called acid indigestion—burning-type pain in the lower part of the mid-chest, behind the breast bone, and in the mid-abdomen. Most children under 12 years with GERD, and some adults, have GERD without heartburn. Instead, they may experience a dry cough, asthma symptoms, or trouble swallowing.

14. Additional information • The digestive that is like a long 30 foot tube, through the middle of the body. Starts at the mouth and finishes at the anus where food leaves the body.

15. Websites for information • Perkins.org • Nutrition.gov • Tutorvista.com • Kidhealth.com • Medical-dictionary.thefreedictionary.com • Sciencebob.com • Buzzle.com • Wisegeek.com • Saylor.org