Digestion is the process of breaking down food into nutrients mixed with various digestive juices, enabling energy, growth and cell repair. The digestive system also entails the elimination of waste. The fluid products of digestion are absorbed across the wall of the gut, usually into some kind of circulatory system which distributes them to the various tissues where they are incorporated into the cells and either built up into complex materials (assimilation) or broken down for energy release (cell respiration).
Mouth and Teeth
The mouth is where the process of digestion starts. Before food enters the mouth, the smell of food triggers the salivary glands to produce saliva. Once food enters the mouth, the teeth cut, tear and grind it which
Bile is stored in the gallbladder when not needed for digestion. When it is needed, it is released into the small intestine.
Duodenum
Peristaltic contractions of the stomach keep the chyme moving towards the duodenum, the first loop of the small intestine. The passage of the into the duodenum is controlled by a ring of muscle, the pyloric sphincter, situated between the pyloric end of the stomach and the duodenum. By contracting and relaxing, the pyloric sphincter can hold food back or let it through. The duodenum is the main part of digestion in the gut.
Pancreas
The pancreas is an accessory organ that produces many digestive secretions and hormones. The hormone that stimulates the pancreas is called secretin. The pancreatic juice flows from the pancreas to the duodenum via the pancreatic duct. The three main pancreatic enzymes are: pancreatic amylase which breaks down starch to maltose, trypsin which breaks down proteins into polypeptides and amino acids and pancreatic lipase which breaks down fat into fatty acids and glycerol. Trypsin is secreted as an inactive precursor trypsinogen. This is converted into trypsin by the action of the enzyme enterokinase, secreted from the wall of the small intestine. The products of amylase and trypsin digestion cannot be absorbed but the fatty acids and glycerol can be. Pancreatic juice is the main source of lipase and completes the digestion of fats. Pancreatic juice
Secretory cells in the wall of the small intestine (duodenum and ileum) produce mucus and a variety of enzymes (intestinal juice) whose collective function is to complete the digestion of the various compounds already started by the other secretions. These enyzmes include maltase which hydrolyses maltose to glucose, therefore completing the digestion of starch, a variety of peptidases which break down polypeptides to amino acids, therefore completing the digestion of proteins; sucrase which hydrolyses sucrose (milk sugar) to glucose and galactose; and enterokinase which activates trypsin. Salts, vitamins and water are also absorbed in the small intestine.
Whilst the food is in the small intestine, it is kept in continual motion by rings of contraction that mix it thoroughly with the various juices secreted into it. This causes rapid digestion. The contractions are stationary or may be moved along the intestine as peristaltic waves which push the food towards to the large intestine. From these activities, the food in the small intestine is converted into a watery liquid called chyle. It is from this that the products of digestion are
a bite of food, your digestive system swings into action. Just the sight or smell, even an enticing description, of some delicious food is enough to make you start salivating and producing stomach acids. Your digestive system is a made up of the gastrointestinal (GI) tract—also called the digestive tract—and the liver, pancreas, and gallbladder. The GI tract is a series of hollow organs joined in a long, tube from the mouth to the anus. The main purpose of the digestive system is to break food into
Digestion is the process in which food is broken down into smaller molecules, that can thereafter be more simply absorbed by the body, producing energy to build and nurture cells. Cells require a continuous amount of energy and nutrients to assist the body in functioning. There are two types of digestion mechanical and chemical. Mechanical digestion is the process of breaking down large food molecules into smaller parts by physical means, taking place in the mouth and stomach. This process typically
All 4 systems, cardiovascular, digestive, respiratory and excretory all aid the body in maintaining homeostasis through the exchange of gases and molecules throughout the body. The respiratory and cardiovascular systems work together to insure all parts of the body have an adequate oxygen supply for every cell to carry out cellular respiration. Deoxygenated blood is pumped from the heart to the lungs where it captures oxygen molecules and transports them from the lungs to around the body until the
REVIEW TASMANIAN DEVILS In short, digestion is the process where food is broken down and then absorbed by the body. The digestive system is extremely important as it is the main factor in how much of a foods nutrients are utilized. The process of digestion is essential for the body as it is the body's source for energy. Tasmanian devils are carnivores, meaning they strictly feed off meat. The main differences that distinguishes a carnivores digestive system with other mammals include the requirement
The food digestion plays an undeniably important role in our body system, which is the main way for the human kind to gain nutrients and energy in order to growth, repairs the body cells, and carry out the daily routine (National Institutes of Health, 2013). The foods and drinks that people consume are required to be turned into the smaller nutrient-molecules before the blood absorbs and carries the various nutrients such as carbohydrates, proteins, fats, vitamins and minerals to the body cells (National
Overview of the Digestive System The purpose of the digestive system is to hydrolyze macromolecules to their smallest subunits. The organs of the digestive system are located within the GI tract. The digestive track is made up of a series of hollow organs joined in a long, twisting tube from the mouth to the anus. The process of digestion requires ingestion, digestion, movement, absorption, and elimination. All parts of the tract have four layers. These layers surround the lumen, or interior space
Objectives The purpose of this report is to make a description of the digestive tracts of pigs and sheep and also to explain briefly the process of digestion on ruminant and non-ruminant organisms. Furthermore there will be an analysis of the results that have been observed on the dissection practical. The report will be finalizing with a comparison between the digestive tract of pig and sheep. Introduction Digestion is the process that the food brake down into smaller components in order to be absorbed
The digestive system is a very important system in the human body. It is a group of organs that work together to turn food into energy and nutrients in the entire body. The food that was chewed in a humans’ mouth now passes through a long tube that is inside of the body that is known as the alimentary canal. The alimentary canal is made of the oral cavity, pharynx, esophagus, stomach, small intestines, and large intestines. Those few things are not the only important accessories of the digestive system
The digestive system is a group of organs that works together to convert food into energy and basic nutrients that will feed the entire body. The digestive system breaks down food so nutrients can be absorbed by the body. The digestive system has three main functions. First, it ingests food then breaks it down so nutrients can be absorbed and it also eliminates what cannot be digested. During an average lifespan, as much as 45 tons of food can pass through one’s digestive system. Food travels almost
The human digestive system is a bodily process made up of many systems, organs and substances that break down food both physically and chemically for use by the body. But what exactly is human digestion and what happens to food as it moves through the digestive system? “…[digestion] is a group of organs working together to convert food into energy and basic nutrients to feed the entire body” (Tim Taylor). There are three major bodily mechanisms that contribute to the process of digestion. The first
The Detail Digestion Process & Body Absorbs of Nutrients Digestion is the chemical breakdown of complex biological molecules into their component parts, i.e. lipids into fatty acids, proteins to individual amino acids, and carbohydrates into simple sugars. The functional objective is to produce various chemicals to break down the food, filter out harmful substances when possible, and get rid of solid wastes. The mechanical way the digestion works in order to change the physical form of the food is
The human digestion system is very complex. It starts with the mouth, salivary glands, pharynx, esophagus, stomach, liver, pancreas, gallbladder, small intestine, large intestine, then ends/exits with the anus. Each step is essential to the whole system. For example, the mouth chews food and mixes it with saliva produced by the salivary glands, and then the pharynx swallows chewed food mixed with saliva, this is followed by the food traveling through the esophagus to the stomach where the food gets
cells directly. The digestive system is responsible for breaking these polymers down into monomers so that the nutrients can be absorbed into the bloodstream and transported throughout the body. This breakdown of nutrients is achieved through mechanical and chemical digestion. Mechanical digestion for all macronutrients begins in the mouth and it involves the physical breakdown of food through tearing, chewing, mixing and churning (Bowers et al., 2002). Mechanical digestion prepares the food for
The digestion lab experiment was conducted for the purpose of understanding digestive enzymes and how they work, and under which conditions they function best. Digestive enzymes are present in the body’s gastrointestinal system and mainly function to break down food into nutrients to be absorbed by the body (Oxford Journal, “The Effect of Enzymes on Digestion). The organs that secrete and/or make use of these digestive enzymes are the mouth, esophagus, stomach, small intestine, large intestine, liver
The Digestive System The digestive system is a group of organs that perform the process by which food, containing nutrients, is eaten and broken down into different components. This breakdown makes it possible for the digested material to pass through the intestinal wall into the blood stream. The digestive process contains many different steps that take place in many different organs.The first step of digestion begins at the mouth, where the food enters the mouth. Saliva is secreted from the