WebThe digestive system includes mouth, salivary glands, liver, gallbladder, appendix esophagus, stomach, pancreas, large intestine and small intestine. The mouth starts the Web7/05/ · Digestive System The gastrointestinal system extends from the mouth to the anus. It includes the oral cavity, esophagus, stomach, duodenum, small and large Web9/07/ · The digestive system involves the breakdown if food into liquids. It is known as the GI tract. The digestive system is important because your body needs nutrients from
Digestive System essays
In this essay we will discuss about the digestive system in humans. After reading this essay you will learn about:- 1. Organs of Digestive System 2. Accessory Glands for Digestion of Foods. Digestion means simplification of complex foods. It is the process of breaking various foodstuff into simple products, digestive system essay. The complex foods like carbohydrates, proteins and fats are converted into glucose, amino acids and fatly acids respectively by the action of digestive enzymes. These simple substances enter into the blood circulation after absorption and then they are utilized by the body. This is also known as digestive tract or gastrointestinal tract. It is digestive system essay long tube of varying diameter which begins at the mouth and ends at the anus. The length of this tube is about meters.
It opens at both the ends. The alimentary canal starts at the mouth into which cavity, the glands of the mouth pour the juice. As it passes backwards, it spreads into a funnel shaped cavity digestive system essay. The tube then narrows into a soft muscular tube about ten inches in long, called the food pipe or gullet. This passes down the neck into the chest. It then opens into the stomach by piercing the diaphragm. The stomach is digestive system essay large bag lying a little to the left under the diaphragm. It has two openings, one where the food pipe ends and the other where the intestines begin. The alimentary canal narrows again and passes into the small intestine which is about twenty two feet in length. The rest of the small intestine is like a coiling tube, whose ends opens into a wide but comparatively short tube known as large intestine.
It is about six feet long. The last part of the Large Intestine is known as Anus. All these digestive glands secrete digestive juices containing different enzymes which digest carbohydrate, protein and fatly foods. Five digestive juices are secreted from digestive glands of the body. The enzymes present in these juices help in the digestion of different types of foods. One digestive juice cannot digest three types of foods i. proteins, fats, and carbohydrates up to their completion, digestive system essay.
One digestive juice cannot digest one particular type of food up to its completion, because food cannot remain in one place for a longer period of time. The medium of action of enzymes present in different digestive juices are different. Some act on digestive system essay medium and some on alkaline medium. The mouth cavity is the front spread out end of the food pipe. The sides of the cavity are formed by the cheeks, the roof by the palate, and the floor by the tongue. When closed, it is bound in-front by the upper and the lower sets of teeth meeting in the middle. The opening at the back of the mouth is known as throat on each side of which there is a mass of tissue called tonsils.
In the outside of the mouth cavity there is a slit like opening which is bounded by two soft movable digestive system essay. These are twenty in number, five in each half of the jaw. They appear at about the age of six months. They are usually smaller and delicate. These are thirty two in number sixteen in the upper and sixteen in the lower jaw, digestive system essay. They appear gradually and push out all the temporary teeth. By the age of 14th, twenty eight permanent teeth are erupting. The last four teeth called as wisdom teeth appear after a person is twenty one years of age.
The tongue is a muscular organ which is present on the floor of the oral cavity. The anterior part of the tongue is small which can move easily into the inner part of the mouth. The taste buds present on the tongue detect the nature of the food. Sweet taste can be felt by the taste buds present in the anterior tip of the tongue and salty taste at a small area behind this tip. Buds at the posterior part of the tongue feel bitter taste and sour taste can be easily known by the taste buds situated in the middle and side area of the tongue. A pair of perotid gland is situated in the cheeks, in front of each ear inside the mouth cavity. They are the largest of the salivary glands.
This is also known as Sub-maxillary gland. A pair of submandibular gland is situated on each side beneath the jaw bone. They are the next largest glands, and are about the size of a walnut. It is the smallest pair of salivary glands. It is present below the tongue. The secretion of these glands is carried through the Duct of Rivinus into the mouth cavity. The salivary glands secrete about to ml of saliva perday. Saliva is a watery alkaline fluid. A starch splitting enzyme known as ptyalin and a bacteriolytic enzyme called as lysozyme are present in saliva. The enzyme ptyalin present in saliva acts on starchy food and converts them to dextrin and maltose, digestive system essay. Salivary juice has antiseptic property. As the food enters into the mouth, digestive system essay, even the smell, the sight or digestive system essay thought of food, the salivary glands are stimulated and saliva is secreted.
This is poured into the mouth. The teeth chew the food and breaks into small pieces while the tongue thoroughly mixes the saliva with the food, digestive system essay. The enzyme ptyalin in the saliva acts on starch and converts it first to dextrins and finally to maltose, digestive system essay. Therefore, it is important to chew the food well to get digestive system essay starch changed into maltose. When some cooked rice or a piece of bread is chewed well digestive system essay mouth, it becomes slightly sweet in taste, because the starch present in them has been changed into sugar, digestive system essay.
Then the digestive system essay food is gathered into a ball digestive system essay bolus and set down the pharynx into the gullet or food pipe. The wind pipe passage for the air is situated in front of the gullet. The food is prevented from going into the wind pipe by a lid like organ called as epiglottis. It is a cartilaginous muscular flap which prevents the entry of food into the windpipe during swallowing and the food enters into the food pipe or gullet. If a particle of solid food or water enters into the wind pipe, it is expelled by violent coughing, digestive system essay. It is a collapsible muscular tube of 9 to 10 inches in length, which extends from pharynx to the cardiac orifice of the stomach.
It passes downwards through the neck, the thorax and the abdominal cavity. The food passes through the oesophagus by peristaltic action. It passes down the food pipe by the action digestive system essay its muscular wall which contract above it and push it along. Food does not simply fall down the gullet, but each part of the gullet contracts after the part next above and so squeezes the food along till it passes through the opening and enters the stomach. The stomach is a digestive system essay part of the alimentary canal. It is a bag like expansion of the food pipe with its broad end to the left and narrow end to the right. It is situated between the oesophagus and the beginning of the small intestine.
It lies close to the diaphragm and slightly towards the left of the abdominal cavity. The size of the stomach varies according to the age and digestive system essay. The stomach consists of an upper part, digestive system essay, the fundus. The main part of the stomach is called the Body and this narrows at its lower end to become the Pyloric Antrum. In the mucous membrane there are a large number of minute blind tubes which are called as gastric glands. These are tiny holes which form the mouth of these gastric glands. When the food enters the stomach, the blood vessels dilate and bring extra blood to the stomach.
Then the gastric glands secrete gastric juice. The gastric juice is poured into the cavity of the stomach and mixed with the food. Besides the gastric glands, the walls of the stomach also contain other glands like pyloric glands, cardiac glands, and mucous secreting cells which secrete mucous, pepsinogen, hormone gastrin etc. Gastric juice is a colourless, acid liquid containing water, minimum quantity of salt, 0, digestive system essay. The stimulation of the secretion of gastric juice is partly nervous and partly chemical. After the food enters the stomach for some fifteen to twenty minutes, the action of saliva continues that is conversion of starchy food to maltose. The gastric juice by that time is secreted in sufficient amount and mixed with the food completely.
When the food of the stomach becomes acidic by hydrochloric acid, the action of ptyalin of saliva stops, because it can act only upon alkaline medium. Then the action of the digestive enzymes present in gastric juice start, as they become active on acidic medium. The enzyme pepsin in the presence of hydrochloric acid acts upon protein food and the casein, and converts them into more soluble substances called peptone. Hydrochloric acid acidifies all foods. Stomach also secretes a protein compound called intrinsic factor which is necessary digestive system essay facilitate the absorption of vitamin from alimentary canal.
What is Digestive system - Definition of Digestive system
, time: 2:02Digestive System Essays: Examples, Topics, Titles, & Outlines
Web7/05/ · Digestive System The gastrointestinal system extends from the mouth to the anus. It includes the oral cavity, esophagus, stomach, duodenum, small and large WebThe digestive system is the the group of organs that changes food to carbohydrates, fats, and proteins and used by our body. Digestion takes places begins form our mouth and Web1/01/ · The human digestive system is responsible for the intake, breakdown, absorption and finally removal of nutrients and energy needed for the functioning of the
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