ch.+8+questions-+rebecca

Chapter 8 Digestive System 1. Describe in you words the processes that occur in the digestive system (ingestion, digestion, movement, absorption, elimination) - In ingestion, th food enters your mouth. Indigestion has to do alot with our diet, and we must have a good healthy diet with lots of nutrients. Digestion can be mechanical or chemical. The food enters teh body and then moves to the small intestine. It breaks up the food into small pieces. Movement is when the food must be passed along from one organ to the next. Movement is important because it helps the tract to fulfill its other functions. Absorption occurs as units molecules produced by digestion cross the wall of the GI tract and enter the cells lining the tract. Nutrients enter the blood. Water can be absorbed. If water is not absorbed, you can become dehydrated Elimination are molecules that cannot be digested and must leave the body. The removal is waste through the anus in the form of feces- defecation.
 * 8.1 Overview of Digestion**

1. Describe the MECHANICAL and CHEMICAL digestion that occurs in the mouth. - Mechanical digestion is when you shew your food with your teeth. You make the food smaller so it becomes easy for you to chew.- The digestive system can take that food and digest it better. -Chemical digestion begins in the mouth and is not completed until food reaches the small intestine. 2. What is heartburn?- Heart occurs due to acid reflux, when some of the stomachs contents escape into the esophagus. 3. What is a dental cavity? (What causes it?)- Dental cavity is tooth decay. The acid causes the tooth to decay when the bacteria metabolizes sugars.
 * 8.2 First Part of the Digestive Tract**

1. What are the functions of the stomach and how is the wall of the stomach modified to perform these functions?- The stomach is a think walled J shaped organ. It is on the left side of the body. The stomach stores food, initiates the digestion of protein and controls the movement of chyme into the small intestine. The stomach does not absorb nutrients. The stomach wall usually has 4 layers, but 2 of them are modified for particular functions. The muscularis contains three layers of smooth muscle.The muscularis allows the stomach to stretch out and it also allows teh stomach to break the food down into small pieces. The mucosa has folds and rugae which allows the stomach to stretch out too. 2. What are the functions of the small intestine and how is the wall of the stomach modified to perform these functions?- The small intestine contains enzymes to digest all types of food, primarily carbohydrates, proteins and fats. The wall of the small intestine absorbs the molecules- mainly sugars, amino acids, fatty acids, and glycerol, which are the products of the digestive system. Nutrients are absorbed in the small intestine. The folds are filled with villi all over the body which absorbs the molecules. 3. What is lactose intolerance? Lactose in sugar in milk.People that cannot digest lactose are lactose intolerant. What causes it and what are the symptoms? People who do not have the brush border enzyme called lactose cannot digest lactose. The symptoms are diarrhea, gas, bloating, and abdominal cramps after drinking milk and other dairy products.
 * 8.3 Stomach and Small Intestine**

1. What are the three main accessory organs and how do they assist the digestive process?- The pancreas- which releases enzymes needed to digest food and to create insulin. The liver- filters the blood of toxins and waste. It makes plasma proteins. It regulates the amount of cholesterol in the blood. 2. What is a gallstone?- A gallstone is when liquid stored in the gallbladder hardens into pieces of stonelike material. 3. What is hepatitis?- Hepatitis is inflammation of the liver. There are 3 types of hepatitis- A, B and C. There are vaccines for A and B, but not for C. You can get hepatitis through contact with blood, unclean needles, or not steral items. Be sure everything that goes into your body is clean. 4. What is cirrhosis?- Cirrhosis is another cirrhosis disease of the liver. It occurs when you drink too much alcohol. Their liver cannot handle all the toxins from the alcohol.
 * 8.4 Three accessory organs.**

1. What is the function of the large intestine? The large intestine is absorbs water, which allows you to stay hydrated. The large DOES NOT produce any digestive enzymes and it does not absorb any nutrients. The large intestine absorbs vitamins produced by bacteria called the intestinal flora. 2. Briefly describe the disorders of the large intestine: diarrhea, constipation, diverticulosis, hemorrhoids, IBS, IBD, polyps, cancer. -diarrhea: is caused by eating contaminated food. Water is not absorbed. When water is not absorbed, dehydration can occur. -constipation: the feces are dry and hard. You become constipated when you ignore the urge to defecate. -Diverticulosis: occurrences of little pouched of mucosa that have pushed out through weak spots in the muscularis. -hemorrhoids: enlarged and inflamed blood vessels at the anus. This is a chronic constipation. This can be caused by pregnancy, aging and anal intercourse. - IBS: Irritable bowl Syndrome: muscularis contracts powerfully but without its normal coordination. The symptoms are abdominal cramps, gas, constipation, and urgent, explosive stools. -IBD: Inflammatory Bowel Disease: Ulcerative colitis and Crohn's disease are the most common. They cause bleeding because they erode the submucosal layer, where nerves and blood vessels are. It also causes diarrhea, rectal bleeding abdominal cramps and urgency. -Polyps: A small growth arising from the epithelial lining. They can be removed by surgery -Cancer: If you get the polyps removed from your colon, the cancer is gone.
 * 8.5 Large Intestine**