Since humans are heterotrophs, they rely on the food they eat to provide their bodies with the energy needed to carry out vital cellular functions. Humans require six essential nutrients for survival: water, vitamins, minerals and three macronutrients; carbohydrates, lipids and proteins (Bowers et al, 2002). These macronutrients are often ingested as polymers, long chains of repeated basic molecular units called monomers, which are too large to be absorbed by 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 chemical digestion by increasing the surface area upon which the digestive enzymes can act (Bowers et al., 2002). In chemical digestion, polymers are broken down chemically through the process of hydrolysis with the aid of digestive enzymes which accelerate the process (Collin County Community College, 2014):
Protein + water protease amino acids
Complex sugar + water carbohydrase simple sugars
Fats + water lipase glycerol + fatty acids
Polymers are formed during dehydration synthesis reactions, as a covalent bond forms between two monomers when a water molecule is lost (Collin County Community College, 2014). In hydrolysis, the covalent bond between monomers in a polymer is broken by the addition of a water molecule as the hydrogen in the water molecule attach...
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...nzymes to digest them. In chemical digestion, hydrolysis breaks the bonds between monomers with the aid of enzymes, secreted throughout the digestive tract and by the accessory organs, to catalyze the process. These enzymes functional optimally in certain areas of the alimentary canal based on the pH of the surroundings. The monomers of carbohydrates and proteins are then absorbed into the mucosal cells of the microvilli lining the small intestine and diffuse into the capillaries surrounding the villi where they are transported in the bloodstream to cells in the body. Most of the nutrient absorption occurs in the duodenum and jejunum (University of Illinois Chicago, 2004). Lipids are too large to diffuse into the capillaries and are reassembled into triglycerides and enter the lymphatic system. Any undigested matter is eliminated from the digestive system as feces.
During digestion, the body breaks down food into smaller molecules that could then be used by the body’s cells and tissues in order to perform functions. This starts off in the mouth with the physical movements of chewing and the chemical breakdown by saliva. Enzymes in the stomach break food down further after traveling from the mouth through the esophagus. The food from here then moves into the small intestine, where pancreatic juices and enzymes dissolve proteins, carbohydrates, and fibers, and bile from the liver breaks down fats into these small molecules. Any portion of the fibers or food that were unable to be broken down are passed from the small intestine to the large intestine, which is where the digestive tract transitions into the excretory tract, then the colon and out of the rectum. Any liquids that have been stripped of their nutrients by the body proceed from the stomach to the kidneys. In the kidneys, sodium ions (Na+), uric acid, and urea are exchanged with water, which moves urinary bladder and is excreted through the
Digestion have a function of breaking down all food into our body. Our body use all nutrients to help in the process been health and growth. Digestion supplied small molecules that will be absorbed into our bloodstream.
The digestive system otherwise known as the gastrointestinal tract (GI tract) is a long tube which runs from the mouth to the anus. It operates to break down the food we eat from large macromolecules such as starch, proteins and fats, which can’t be easily absorbed, into readily absorbable molecules such as glucose, fatty acids and amino acids. Once broken down, these molecules can cross the cells lining the small intestine, enter into the circulatory system and be transported around the body finally being used for energy, growth and repair.
The enzyme pancreas amylase causes the decomposition of starch. The starch during the chemical reaction broken down into disaccharides, lactase, sucrase, and maltase forms of pure sugar. Disaccharides are broken down to monosaccharides. Lactase changed into lactose, then into glucose and galactose sucrase changed sucrose into glucose and fructose these are all forms of sugars. These sugar may not all be utilized by the body. Maltase breaks down maltose 2 form molecules of glucose. Protein -stomach Pepcid and HCI break down proteins. These protein continue during the chemical reaction change to polypeptides. In the small intestines- Trypsin breaks down proteins and polypeptides to dipeptides. Then the dipeptides are changed into chymotrypsin decomposition of proteins and polypeptides to dipeptides. Carboxypeptidase breaks down polypeptides and dipeptides to amino acids. Aminopeptidase disintegrates of polypeptides & dipeptides to amino acids. Dipeptidase dissects of dipeptides to amino acids. Amino acids are more utilized by the digestive process; they are the building blocks of protein. Fats start the chemical digestive process in the mouth, this maybe because that many fats take longer to decompose. Lingual lipase has a minor role in beginning fat digestion. The stomach has an immense amount of chemical reaction going on at one time.
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 Institutes of Health, 2013). According to National Institutes of Health (2013), the decomposition of food nutrients are completed through the digestive system which form by the gastrointestinal (GI) tract, also defined as digestive tract, and along liver, pancreas and gallbladder as well. The GI tract is made up of a series of hollow organs with the connection from mouth to anus, which consisting buccal cavity (mouth), esophagus, stomach, small intestine, and large intestine. Based on Batrisya (2013), the food digestive process are classified into four stages, that are ingestion, digestion, absorption, and egestion or elimination (refer to Figure 1 in Appendix 1).
Digestion is the breakdown of food that allows the body to absorb the food into the bloodstream and into the cells for energy. This happens mechanically and chemically, mechanically means by your teeth, tongue and gums so chewing food. Whereas chemically means by the digestive enzymes; amylase, protease and lipase.
Digestion is defined as the process of transforming foods into unites for absorption. The Digestive System is a complex network of organisms that have six major processes: The digestion of food, the secretion of fluids and digestive enzymes, the mixing and movement of food and waste throughout the body, the digestion of food into smaller pieces, the absorption of nutrients, and the excretion of wastes (Inner Body (1).)
...ve eaten, to break down the food into a liquid mixture and to slowly empty that liquid mixture into the small intestine. Once the bolus has entered your stomach it begins to be broken down with the help of the strong muscles and gastric juices which are located in the walls of your stomach. The gastric juices are made up of hydrochloric acid, water, and mucus- and the main enzyme inside of your stomach is what is known as pepsin, which needs to be surrounded in an acidic setting in order to do its job, that is to break down protein. Once the bolus has been inside of your stomach for long enough it begins to form into a liquid called chyme, and what keeps the chyme from flowing back into our esophagus are ring shaped muscles known as sphincters located at the beginnings and ends of the stomach and they have the task of controlling the flow of solids and liquids.
...he Buttermilk White bread. The food makes its way to the transverse colon and extra nutrients are released form the cellulose of the undigested particles. It continues on to the descending colon. There I start to manufacture vitamin K and other B-complex vitamins. Those are then absorbed into my large intestine.
Imagine you are eating a sandwich containing wheat bread, ham, lettuce, and Swiss cheese. Do you ever wonder where the nutrients go from all of the previous listed ingredients? Well, when a bite of this sandwich is taken, the mouth produces a saliva enzyme called amylase. This enzyme immediately goes to work by breaking down the carbohydrates that are in the bread. Once, the bite is completely chewed, the contents then are swallowed and go down the esophagus and begin to head towards the upper esophageal sphincter and the is involuntarily pushed towards the stomach. The next passage for the sandwich is to go through the lower esophageal sphincter; which transports the sandwich into the stomach.
The digestive system is important for breaking down food and turning it into nutrients. The body uses the nutrients for energy, growth, and cell repair. The food and drinks that a person must be changed into smaller molecules of nutrients before the blood absorbs them and carries them to cells throughout the body. The body breaks down nutrients from food and drink into carbohydrates, protein, fats, and vitamins. Compared to the other systems in the body, the digestive system is one of the most diverse and important. According to Robert Sullivan the digestive system is a set group of organs whose function is based on the process of turning food, absorbing nutrients for energy and getting rid of the bodies waste (Sullivan, 2008, p.33). The organs
When eaten, protein is broken down into amino acids. Proteins and amino acids are used for almost every metabolic process in the body, and are the building blocks for every tissue in your body.
The synthesis of polymers starts with ethylene, (or ethene). Ethylene is obtained as a by-product of petrol refining from crude oil or by dehydration of ethanol. Ethylene molecules compose of two methylene units (CH2) linked together by a double carbon
If you frequent health forums or fitness blogs, you'll have read the word “macros” before. The word is short for macronutrients. That leads to the question, “what are macronutrients?”
It is then secreted within the small intestine where it helps to break down ethanol, fats and other acidic wastes including ammonia, into harmless substances.