Digestive+System+MV

Molly Vaughn 04 September 2008 Human Biology

8.1 Overview of Digestion 1. Name and describe the three processes that occur during the digestive process. - Ingestion is when the body takes food or liquid into the body by way of the mouth. - Digestion is the breaking down of large nutrient molecules into smaller molecules that can be absorbed. - Absorption is the taking in of substances by cells or membranes.

2. What are the four layers of the GI tract? Associate an illness with each of the layers. Describe the illness.

8.2 The First Part of the Digestive Tract Define the following voca8.1 Overview of Digestion 1. Name and describe the three processes that occur during the digestive process. 2. What are the four layers of the GI tract? Associate an illness with each of the layers. Describe the illness.

8.2 The First Part of the Digestive Tract Define the following vocab Palate: Skin on the roof of the mouth. Salivary glands: Gland associated with the mouth that secretes saliva. Dental carries: Tooth decay that occurs when bacteria within the mouth metabolizes sugar and give off acids that erode teeth; a cavity. Periodontitis: Inflammation of the periodontal membrane that lines tooth sockets, causing loss of bone and loosening of teeth. Pharynx: Portion of the digestive tract between the mouth and the esophagus that serves as a passageway for food and also for air on its way to the trachea. Esophagus: Muscular tube for moving swallowed food from the pharynx to the stomach. Glottis: Opening for airflow in the larynx. Epiglottis: Structure that covers the glottis during the process of swallowing. Peristalsis: Wavelike contractions that propel substances along a tubular structure, such as the esophagus. Sphincters: Muscle that surrounds a tube and closes or opens the tube by contracting and relaxing. Diaphragm: Dome-shaped horizontal sheet of muscle and connective tissue that divides the thoracic cavity from the abdominal cavity.

3. Describe the mechanical and chemical digestion that occurs in the mouth. 4. What ordinarily prevents food from entering the nose or entering the trachea when you swallow? The glottis prevents food from entering the nose or entering the trachea when you swallow.

Health Focus Heartburn (p148) 5. What causes the burning sensation associated with heartburn? The burning sensation associated with heartburn is due to acid reflux. 6. What is GERD? How is it different from heartburn? GERD is a patient that is diagnosed with gastro esophageal reflux disease. The difference between GERD and heartburn is that a person with GERD will experience acid reflux more often and it can usually cause pain in the chest, choking, and having trouble to swallow. 7. Describe two ways drugs treat GERD. The two ways that drugs treat GERD is to neutralize stomach acid and shut down and reduce acid production. 8. Describe ways to avoid heartburn that do not involve drugs. It has been found that diet can help control acid reflux without any use of drugs.