Digestion+questions

1. Processes of the digestive system -	Ingestion is the process of taking in food. It involves chewing and grinding by the teeth and tasting by the tongue. Swallowing is also a part of ingestion. -	Digestion is a mechanical and chemical process of the digestive system. The Mechanical part begins in the mouth, with chewing. The chemical part begins in the mouth as well as saliva mixes with food and breaks it down with enzymes. -	Movement in the digestive system involves the GI tract. Food is passed along this tract as each individual organ does its job. Movement bring food into the body and also cause it to leave the body. -	Absorption in the digestive system occurs mostly in the intestines. During this process, nutrients from food are absorbed from the GI tract into the cells of the body. -	Elimination is the getting rid of wastes that must occur in the body. Unused molecules, or those that cannot be digested, leave the body usually in the form of feces.

2. Layers of the digestive tract - The innermost layer of the GI tract is the mucosa. Diverticulosis is a condition in which pockets form in this layer. Food collects in the pouches and become inflamed. - The next layer of the digestive tract is the submucosa. This layer involves the lymph nodes and nerves. Inflammatory response in the blood vessels of the layer may cause chrominc diarrhea, abdominal pain, fever, and weight loss in a condition known as inflammatory bowel disease. - The third layer in the tract is the muscularis. The muscles of this layer move food through the digestive system system. Irritable bowel syndrome is a condition in which irregular muscular movement in this layer cause abdominal pain, constipation and diarrhea. - The outside layer of the tract is the serosa. The appendix is an extension of this layer, and an inflamed appendix may lead to peritonitis, a serious infection.

3. In the mouth, chemical digestion occurs when food comes in connect with the salivary amylase enzyme in saliva. This enzyme begins to break down food. Teeth and the tongue go on to perform mechanical digestion in the mouth. Teeth grind the food into smaller pieces, and the tongue is signaled by the brain to form the food into a mass called a bolus. The bolus is then pushed down the throat.

4. The soft palate of the mouth prevents food from traveling up the nasal passage while the trachea and epiglottis work together to cover the opening to the voice box. This movements together prevent food from “going down the wrong pipe.”

5. The stomach stores food, begins the digestion of protein, and controls movement of food into the small intestine. The wall of the stomach has an extra layer of muscle that runs obliquely to the other layers. The stomach also secretes gastric juices with strong acids that further break down food. 6. The small intestine completes the process of digestion and also absorbs nutrients. It digests carbohydrates, proteins, and fats with a substance secreted by the gallbladder called bile. The small intestine has an incredibly large surface area in order to absord nutrients. The mucosa of the small intestine is covered in villi as well, that bring nutrients into the cells.

7. Three main accessory organs involved in the digestive system are the pancreas the liver, and the gall bladder.

8. The pancreas produces pancreatic juices which have enzymes that help food to digest. Starch is digested by pancreatic amylase, protein by trypsin, and fat, by the enzyme lipase. The liver detoxifies the blood. In the digestive system, the liver helps to form a waste product called urea. The gallbladder produces bile which helps to break down fat in the digestive system.

9.The parts of the large intestine include the cecum, the colon, the rectum, and the anal canal.

10. The large intestine prevents dehydration in the body by absorbing water. It also absorbs vitamins, and forms feces. The large intestine is further in charge of defecation, or the getting rid of wastes in the body.