Accessory Organs The Liver Gallbladder And Pancreas

The liver and the gallbladder are two important accessory digestive organs that work with the small intestine. The liver Figure 6.3 Villi and microvilli (illustrated here) act to increase the surface area of the small intestine, thus increasing the potential for nutrient absorption. Villi are finger-like projections on the surface of the intestine, and microvilli are smaller projections stemming from the villi. Figure 6.3 Villi and microvilli (illustrated here) act to increase the surface area...

Your Health Heartburn

Heartburn occurs when the stomach contents pass back up into the esophagus. This regurgitation can occur when the person vomits, the stomach is overfull, or the person is obese, pregnant, or running. The cardiac sphincter and the diaphragm do not entirely close off the connection to the stomach. It is fairly easy to overcome these barriers and bring stomach contents back up into the tube. Because the pH of the stomach fluids is usually below 4, or about the strength of a car's battery acid, the...

Your Health Empty Calories

Sometimes foods are described as having empty calories. This means that the item is made mostly of sugar, probably sucrose, and not much of anything else. When carbohydrates are ingested along with proteins, lipids, vitamins, and minerals, they form part of a balanced diet that fills our nutritional needs. of proteins starts out simple, and then becomes more complex, depending on the protein. The function of the protein depends on its structure. The chain of amino acids will bend and twist to a...

Fad Diets

Currently, there are many fad diets being advertised. Some recommend eating all protein, while others recommend special drinks or pills. No matter what the fad diet, unsound weight loss programs tend to have some similar characteristics. They promise dramatic weight loss over a short period of time they recommend eating an extremely low number of calories, usually without medical supervision and they frequently try to make adherents to the diet depend on certain foods, usually provided by them...

Food Pyramids Obesity And Diabetes

An estimated 60 of Americans are overweight and 25 are obese. Obesity can be measured in several ways. One method states that if a person weighs more than 20 of the ideal weight according to the height weight chart, the person is obese. This method does not take into account an athlete who may weigh more than a nonathlete because of muscle, not fat. Another method of measuring obesity is to measure percentage of body fat. If a person's body fat is more than 25 for a man or 30 for a woman, that...

Large Intestine Anatomy And Digestion

Rectum And Anal Canal Anatomy

The large intestine (Figure 7.1) is a tube about 5 feet long and Figure 7.1 The large intestine consists of the cecum, colon, rectum, and anal canal. It is last place where the body will remove nutrients before the waste is excreted. Figure 7.1 The large intestine consists of the cecum, colon, rectum, and anal canal. It is last place where the body will remove nutrients before the waste is excreted. 2.5 inches in diameter. It is wider than the previous sections of the digestive tube and can...

Structure Of The Digestive Tube

Four Walls The Digestive Tract

Throughout the digestive tube, the walls of the organs are made up of four layers mucosa, submucosa, muscularis, and the serosa or adventitia (Figure 4.2). The innermost layer of the digestive tube is the mucosa. This layer is composed of three parts the epithelium, the lamina propria, and the muscularis mucosae. The innermost part of the mucosa is the epithelium. Most of the epithelial layer is made up of a single layer of cells called columnar epithelial cells. These cells are lined up like...

Digestion In The Small Intestine

Fat Absorption

When acidic chyme enters the duodenum, it triggers several events. The acid, along with short proteins called peptides and fatty acids in the chyme, causes cells at the beginning of the duodenum to secrete intestinal fluid. About 1 to 2 quarts of this digestive fluid is produced each day. The intestinal juice, which contains some mucus, is alkaline and helps to neutralize the acidic nature of chyme and protect the duodenum from the effects of the acid. The chyme also causes the release of two...

Robert J Sullivan

President and Surgeon-in-Chief of the Texas Heart Institute Clinical Professor of Surgery at the University of Texas Medical School, Houston, Texas A Haights Cross Communications Company Philadelphia Copyright 2004 by Infobase Publishing All rights reserved. No part of this book may be reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying, recording, or by any information storage or retrieval systems, without permission in writing from the...

Digestion Absorption and Elimination

Let's get back to Amy and her lunch mentioned in Chapter 1. She will eat her hamburger, fries, and chocolate shake, but how do these nutrients get to the tissues in the body that need them Digestion is the process of preparing foods to enter the body. This may sound strange, but any foods inside the digestive system are not yet actually in the body. The digestive system is a long tube (about 30 feet when relaxed) with openings at both ends (Figure 4.1). This tube is contained within the body...