Digestive Process

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The Digestion process
The digestive process is important in maintaining the lives of living organisms and in providing them with needed energy and nutrition. Groups of organs, such as the mouth, esophagus, stomach, intestines, pancreas, and gal bladder work together to perform this complex task. Digestion is the process of breaking down food from large molecules into small ones to make it easier for absorption. The three major steps involved in the digestive process are ingestion, digestion, and absorption.   Ingestion, which occurs in the mouth, is the first step of the digestive process. After food enters the mouth, the teeth chew it. Saliva, which is produced by the salivary glands, plays a major role in breaking down the food into smaller pieces, such food particles, like Starch, which is digested by amylase. A large amount of saliva is amylase based, it is in fact, the first enzyme that comes into contact with your food/substrate during the process of digestion. Once the food has been chewed it turns into a paste like substance, and is found in tiny clusters, this is called a bolus. The bolus travels to the stomach through the esophagus. The stomach is a c-shaped organ that valves at both ends, these valves are circular muscles, and are usually referred to as sphincters. The sphincter that closes the stomach at the esophagus end is called the cardiac sphincter; the one found at the opposite end is called the pyloric sphincter. The stomach lining is muscle, the function for this, is so that it can undergo churning movements to mix the stomach contents to form what is called chyme. Another adaptation of the stomach is the lining which is folded to increase the surface area in which it can secrete gastric juices.   In the stomach, the second step of the digestive process begins. When the bolus reaches the bottom of the esophagus, the cardiac sphincter lets the food enter the stomach. Contractions of the stomach walls mix the food. Acidic gastric juices, which...
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