Chapter+8+Homework+Questions

Chapter 8 Digestive System 8.1 Overview of Digestion 1. Describe in you words the processes that occur in the digestive system (ingestion, digestion, movement, absorption, elimination) Ingestion- this is the process of takin food in through the mouth. Your teeth chew everything up enough so that it may be swallowed to move onto the next phase. Digestion- this process is the next step in line, and it can be either mechanical or chemical. mechanical is the process in which food is divided into smaller pices that can be used by the digestive enzymes. chemical digestion starts right when the food comes into the mouth, and isn't complete untill the food goes all the way down to your small intestine. Movement- is the process of passing along the food from organ to organ, and each time this occurs the food gets broken down a little bit further while the organ takes what it needs before passing it on. Absorption- is when molecules cross the GI tract and go into the cells lining the tract, once this occurs they can then get into the blood and deliver directly to the cells. Elimination- this is when the food has reached the end of its journey, and everything that the body has not been able to absorb must leave the body since there is no use for it, leading up to you having to go to the bathroom. 8.2 First Part of the Digestive Tract 1. Describe the MECHANICAL and CHEMICAL digestion that occurs in the mouth. The mouth is where the entire process begins. first your teeth chew and grind up the food, and your tongue helps push everything around and then you swallow so the food can go down your esophagus. This process is also known as ingestion, the process of taking in food. 2. What is heartburn? This is caused by acid reflex. it happens when some of the stomach's acid gets into your esophogus/throat making you feel really weak or out of breath. in some cases you have to throw up, because the abdominal muscles contract. 3. What is a dental cavity? (What causes it?) This happens when the mouth has sugar in it that give off acids that are very bad for the theeth. as a result these acids begin to wear away the teeth, also known as tooth decay, and can sometimes erode all the way down to a nerve in your tooth. 8.3 Stomach and Small Intestine 1. What are the functions of the stomach and how is the wall of the stomach modified to perform these functions? The purpose of the stomach is to further break down food to the point of where it can be absorbed by other cells, so in a since it makes them near microscopic. the stomach acieves this by using acids to boil down the food wich then turns into slushy stuff and is carried straight down into your intestine (small). The stomach is allowed to expand depending on how much food intake occurs during one meal, which means that it can modify depending on what kind of or how much food you are eating. 2. What are the functions of the small intestine and how is the wall of the small intestine modified to perform these functions? The main purpose of the small intestine is to finish up the digestion process. every nutriant that is needed by cells is extracted in the small intestine, which means that everything that comes out of the small intestine the body must disguard because it is of no further use. 3. What is lactose intolerance? What causes it and what are the symptoms? This is when people lack an enzyme that allows them to digest milk. If you are unable to yet you still have some, this can lead to diarrhea, gas, and bloating. all of these things can cause much discomfort to the body, so all of the people that are lactose intolerant must not digest any form of milk at all. 8.4 Three accessory organs. 1. What are the three main accessory organs and how do they assist the digestive process? The Pancreas- is responsible for secreting the hormone insulin into the blood. It produces sugar in your body, which is critical to a person being able to live. The Liver- which happens to be the largest metabolic gland that the body possesses. Its job is to filter out all of the crap that a person drinks. think of it as an air filter in your house, its job is to collect all of the bad stuff that comes in through its vent, but over time it begins to wear out. another one of the liver's functions is to break down hemoglobin, and as a result out comes bile. The Gallbladder- this is the organ that is used to store or concentrate bile in the body. 2. What is a gallstone? They form when the liquid that is stored up in the gallbladder hardens into really had stones. this can be very painful and hard to get rid of as a result. 3. What is hepatitis? Hepatitus is known as the inflammation of the liver, and you can get viral hapatitis is several different forms, such as through sex, needles, and many other ways. 4. What is cirrhosis? This is considered to be an invisible injury to the tissue of the liver, and is caused by consumption of large quantities of alchol over a period of time. 8.5 Large Intestine 1. What is the function of the large intestine? This is the last stop for food on the digestion track, so every bit of protein and nutriants are extracted right here before the body gets rid of whats left. friendly bacteria also hang around in the large intestine for the free food that comes their way every day. 2. Briefly describe the disorders of the large intestine: diarrhea, constipation, diverticulosis, hemorrhoids, IBS, IBD, polyps, cancer. Diarrhea- when your body is dehydrated, and thus your bowel movements are very wattery since the water can not be absorbed Constipation- the process of where your bowel movements are delayed and is caused by not having enough water in your fecies Hemorrhoid- this is when you pop a blood vessel in your rectum Cancer-an out of control tumor, whose cells have no control over their growth and also have the ability to invade tissue and metastasize.