The organs of the gastrointestinal tract are arranged in such a way that a person receives from food all that is necessary for their vital activity. What important functions do digestive organs perform? Thanks to their well-coordinated work, toxins and poisons do not enter the blood. In addition, the digestive system protects a person from certain infectious diseases and allows his body to synthesize vitamins on its own.
Structure and function of the digestive organs
The digestive tract consists of the following links:
- oral cavity with salivary glands;
- pharynx;
- esophagus;
- stomach;
- the liver;
- large and small intestines;
- pancreas.
| Name of authority | Structural features | Functions |
| Oral cavity | Tongue, teeth | Grinding, analysis and softening of the food lump |
| Esophagus | Muscular, serous membranes, epithelium | Motor, protective and secretory functions |
| Stomach | It has a large number of blood vessels. | Digestion of food bolus |
| Duodenum | Includes the ducts of the liver and pancreas. | The movement of the food bolus in the digestive tract |
| Liver | It has veins and arteries that are responsible for the blood supply to the organ. | The distribution of nutrients, the synthesis of various substances and the disposal of toxins, the production of bile |
| Pancreas | Is under the stomach | Extraction with enzymes of a special secret that modifies nutrients |
| Small intestine | It is arranged in loops, the walls of this organ can contract, on the inner mucosa there are villi, increasing its area | Absorption of split beneficial substances |
| Large intestine (with anus and direct section) | The walls of the body are made up of muscle fibers. | Completion of the digestive process, as well as the absorption of water, the formation of feces and bowel emptying through the act of defecation |
The digestive tract looks like a tube between seven and nine meters long. Some glands are located outside the walls of the system, but interact with it and perform common functions. Interestingly, the gastrointestinal tract has a greater length, but fits inside the human body due to the huge number of bends and loops of intestines.
Functions of the digestive system
The structure of the human digestive organs, of course, is of considerable interest, however, the functions that they perform are also curious. First, the food lump through the mouth enters the pharynx. Then he moves to other parts of the digestive tract along the esophagus.
The food crushed in the mouth and processed with saliva enters the stomach. In the abdominal cavity are the organs of the final segment of the esophagus, as well as the pancreas and liver.
The duration of the stay of food in the stomach depends on its type, but is not more than a few hours. Food located in the specified organ interacts with gastric juice, as a result of which it becomes very liquid, it is mixed and later digested.
Further, the mass enters the small intestine. Thanks to enzymes (enzymes), nutrients are converted into elemental compounds that are absorbed into the circulatory system, before being filtered in the liver. Residues of food are advanced into the large intestine, where fluid is absorbed and feces are formed. With the help of defecation, processed food leaves the human body.
The value of saliva and esophagus in the digestive system
The organs of the digestive system cannot function normally without the participation of saliva. On the mucous membrane of the oral cavity, where food initially falls, small and large salivary glands are located. Large salivary glands are located near the auricles, under the tongue and jaws. The glands, localized near the auricles, produce mucus, and the other two species - a mixed secret.
The separation of saliva can be very intense. So, when drinking lemon juice, up to 7.5 ml of this liquid is released per minute. It contains amylase and maltase. These enzymes activate the digestive process already in the oral cavity: under the action of amylase, starch is converted into maltose, which is then maltase modified to glucose. An impressive part of the saliva is water.
A food ball is in the mouth for up to twenty seconds. During this time period, starch cannot fully dissolve. Saliva, as a rule, has either a slightly alkaline or neutral reaction. In addition, in this fluid there is a special protein lysozyme, which has disinfecting properties.
Human digestive organs include the esophagus, which follows the pharynx. If you imagine its wall in section, you can see three layers. The middle layer consists of muscles and can shrink, which makes it possible to “travel” the food bolus from the pharynx to the stomach.
With the passage of food along the esophagus, the stomach sphincter is triggered. This muscle prevents the backward movement of the food lump and holds it in the specified organ. If it does not work well, the processed mass is thrown back into the esophagus, which leads to heartburn.
Stomach
This organ is the next after the esophagus link of the digestive system and is localized in the epigastric region. The parameters of the stomach are determined by its contents. The body, free from food, has a length of no more than twenty centimeters and a distance between the walls of seven to eight centimeters. If the stomach is moderately filled with food, then its length will increase to twenty-five centimeters, and the width to twelve centimeters.
The capacity of an organ is variable and depends on its content. It ranges from one and a half to four liters. When performing the act of swallowing the muscles of the stomach relaxes until the end of the meal. But all this time his muscles are at the ready. Their value cannot be overestimated. The food is frayed, and thanks to the movement of the muscles it is processed. Overcooked food lump moves to the small intestine.
Gastric juice is a clear liquid with an acidic reaction, due to the presence of hydrochloric acid in its composition. It contains the following groups of enzymes:
- protease cleaving proteins to polypeptide molecules;
- lipases affecting fats;
- amylases that convert complex carbohydrates into simple sugars.
The production of gastric juice is usually carried out during the use of food and lasts from four to six hours. In 24 hours, up to 2.5 liters of this liquid is released.
Small intestine
This segment of the digestive system consists of the links listed below:
- duodenal ulcer;
- lean intestine;
- ileum.
The small intestine is “packed” in loops, thanks to which it fits in the abdominal cavity. He is responsible for continuing the process of processing food, its mixing and subsequent direction to the thick section. The glands located in the tissues of the small intestine produce a secret that protects its mucosa from damage.
In the duodenum the environment is slightly alkaline, but with the penetration into it of the mass of the stomach changes in a smaller direction. In this zone is the pancreatic duct, the secret of which alkalizes the food lump. It is here that enzymes of the gastric juice cease to function.
Colon
This section of the gastrointestinal tract is considered to be final, its length is approximately two meters. It has the largest lumen, however, in the descending colon department the width of this organ decreases from seven to four centimeters. The structure of the large intestine includes several zones.
Most of the time, the food lump is in the large intestine. The process of digesting food itself takes from one to three hours. In the large intestine is the accumulation of the contents, the absorption of substances and fluids, moving them along the tract, the creation and elimination of feces.
As a rule, food reaches the large intestine approximately three hours after the end of the meal. This segment of the digestive system is filled within one day, and then gets rid of food debris for 1-3 days.
In the large intestine is the absorption of nutrients produced by the microflora that lives in this department, as well as an impressive part of the water and various electrolytes.
The effect of alcohol on the digestive tract
The negative effect of alcohol on the state of the gastrointestinal tract begins in the oral cavity. High concentrations of ethanol provoke a decrease in the separation of saliva. This fluid has bactericidal properties, that is, it disinfects plaque microorganisms. With a decrease in its quantity, the oral cavity becomes a suitable place for the development of diseases. Carcinoma of the throat and oral cavity, unfortunately, is often found among drinkers.
With regular use of alcohol, the protective mechanisms of the body deteriorate. Their poor quality work affects the functioning of the digestive tract. The esophagus is primarily affected. A person who is confronted with alcohol dependence often has difficulty in swallowing, and sometimes food that has entered the stomach is thrown back into the esophagus.
An addiction can lead to the development of gastritis and a worsening of the secretory function. Ethanol has a negative effect on the work of the pancreas. In addition, frequent use of alcohol increases the risk of pancreatitis, which can occur in acute or chronic form.
The most well known consequence of alcohol addiction is cirrhosis. Unfortunately, it often develops into liver cancer. Cirrhosis is not the only disease that develops in people who are dependent on alcohol. There are also pathologies such as hepatomegaly and hepatitis. Their treatment requires a competent approach.
Thus, the system of the digestive organs consists of several links, whose well-coordinated work largely depends on human health. It is thanks to the digestive tract, the body receives all the nutrients it needs for normal life.
The liver plays an important role: it disinfects toxins and other harmful compounds that enter it through the portal vein. She spends enormous energy on her work. Since this body is considered a kind of "filter", the state of human health depends on the quality of its work.
The negative effect of alcohol on the digestive system should not be underestimated. Regular consumption of beverages containing ethanol provokes the development of various gastrointestinal diseases, which are not always curable. Addiction to addiction badly affects the work of the organism as a whole.
The structure of the digestive system:
1. Oral cavity;
2. Throat;
3. Esophagus;
4. Stomach;
5. Liver;
6. Pancreas;
7. Small and large intestine.
1. Oral cavity.
Teeth grind food, using tongue to mix it with saliva. Saliva is produced by small (located in the thickness of the mucous membrane near the teeth) and large (parotid, submandibular and sublingual) glands.
2. Throat.
The pharynx is a funnel with a tube of 12-15 cm, suspended from the base of the skull, serves not only to transfer the food lump, but also to air.
3. Esophagus.
The esophagus - has the form of a hose 1/4 m long, connects the pharynx to the stomach. The wall of the esophagus is lined inside with epithelial tissue, has a pronounced muscle layer and sphincters. Muscles are needed to push the food further with their cuts, and sphincters (reinforced rings) do not allow it to go back.
4. Stomach.
The stomach is a hollow education. The wall has 3 layers. In an adult, the volume of this organ goes up to 4 liters, the length to food is 18–20 cm, with a filling of 24–26 cm.
Function:
The mucous produces gastric juice. With it, the processing of food continues. Read more about the structure of the human stomach.
5. Duodenum.
At the very beginning of the small intestine is the duodenum.
Function:
It receives the secret of the pancreas, bile from the liver for further digestion.
6. Small intestine.
The entire small intestine is 2.2–4.5 m long, 4.7 mm in diameter. In men, it is slightly longer than in women.
Function:
The mucosa of the small intestine also secretes its secret for the final processing of nutrients. Here, the splitting comes to the degree of protein molecules and individual chemicals. Through the wall of the small intestine, the body's necessary substances are absorbed into the bloodstream.
7. Large intestine
In the colon ends digestion of food. It begins in the chest, goes into the abdominal cavity and descends into the pelvis. Its length is 1-1.7 m, the lumen is 4 - 8 cm. It ends up with an anus - an external opening for the extraction of waste slags.
8. Liver.
The liver has a mass of 1.5 kg. This is a “factory” for processing all incoming toxins, poisons, building protein, certain hormones, blood cells, metabolizes, stores energy in the form of glycogen.
9. Gall bladder.
Gall bladder is like a pear. Its capacity 40-60 ml, accumulates, produced by liver cells, bile and transmits it to the duodenum. Located in front of the right lobe of the liver.
10. Pancreas.
Pancreas - is involved not only in the process of digestion with the help of its juice, but also contains special cells that produce the hormone insulin. Insulin is needed to break down glucose and produce energy. Its length in an adult up to 18 cm, width 3-9 cm, thickness 20-30 mm.
For clarity, the picture, all the basics wrote, choose the most important for you, you can not write some data just for self-development :) Good luck.
Proper work of all organs of the human body - the guarantee of health.
At the same time, the digestive system is one of the most important, as it involves the daily performance of its functions.
Structure and function of the human digestive system
The components of the digestive system are the gastrointestinal tract (GIT) and supporting structures. . The entire system is conventionally divided into three sections, the first of which is responsible for mechanical processing and processing, in the second section the food is subjected to chemical processing, and the third is designed to bring unused food and excess food out of the body.
Based on this separation, the following functions of the digestive system arise:
- Motor. This function involves the processing of food mechanically and its promotion along the gastrointestinal tract (food is ground, mixed and swallowed by humans).
- Secretory. In the framework of this function, the production of special enzymes that contribute to the formation of conditions for the chemical treatment of the incoming food occurs.
- Suction To perform this function, the villi of the intestine absorb nutrients, then they enter the blood.
- Excretory. As part of this function, substances that are not digested or are the result of metabolism are eliminated from the human body.
Human digestive tract
It is advisable to begin the description of this group with the fact that the gastrointestinal tract involves the composition of 6 separate elements (stomach, esophagus, etc.).
Separately, motor, secretory, absorption, endcretory (consists in the production of hormones) and extremum (consists in excretion of metabolic products, water and other elements) are studied as tract functions.
Oral cavity
The oral cavity acts as the initial part of the gastrointestinal tract. It becomes the beginning of the process of food processing. Mechanical processes produced cannot be imagined without the participation of the tongue and teeth.
Such processes do not do without the work of auxiliary structures.
Pharynx
The pharynx is an intermediate between the oral cavity and the esophagus. The human pharynx is presented in the form of a funnel-shaped canal, which narrows as it approaches the esophagus (the wide part is at the top).
The principle of the pharynx is that food enters the esophagus by swallowing portions, but not all at once.
Esophagus
This section connects the pharynx and the stomach. Its location starts from the chest cavity and ends in the abdominal cavity. Food passes through the esophagus in seconds.
Its main purpose is to prevent food from moving back up through the alimentary canal.
The structure of the human stomach
Physiology assumes such a device of the stomach, the functioning of which is impossible without the presence of three membranes: the muscular layer, the serous membrane, and the mucous membrane. In the mucosa produced nutrients. The remaining two shells are designed to protect.
In the stomach, there are processes such as processing and storage of incoming food, splitting and absorption of nutrients.
Human intestinal structure
After staying processed food in the stomach and performing a number of functions in the relevant departments, it enters the intestine. It is designed in such a way that involves the division into the colon and large intestine.
The sequence of the passage of food is as follows: first, it enters the small intestine, and then into the colon.
Small intestine
The small intestine consists of the duodenum (the main stage of digestion occurs here), the jejunum and the ileum. If you briefly describe the work of the duodenum, then it neutralizes the acid, and the substances and enzymes are split. Both the jejunum and the ileum are actively involved in the process of absorption of important elements by the body.
Colon
In the large intestine, the final part of food processing takes place. The first section of the colon is the cecum. Then the food mixture enters the colon, after which the principle of the sequence of passing through the ascending, transverse, descending and sigmoid colon works.
Then the food mixture enters the rectum. In the colon, substances are finally absorbed, the process of the formation of vitamins takes place and feces are formed. The colon is by right the largest division of the digestive system.
Subsidiary bodies
Auxiliary organs consist of two glands, a liver and a gallbladder. The pancreas and liver are considered large digestive glands. The main function of excipients is to promote the digestive process.
Salivary glands
The location of the work of the salivary glands is the oral cavity.
With the help of saliva, particles of food are soaked and easier to pass through the channels of the digestive system. At the same stage begins the process of splitting carbohydrates.
Pancreas
Iron refers to the kind of organs that produce hormones (such as insulin and glucagon, somatostatin and ghrelin).
In addition, the pancreas secretes an important secret, it is necessary for the normal functioning of the food digestion system.
Liver
One of the most important organs of the digestive system. It cleanses the body of toxins and unwanted substances.
The liver also produces bile, necessary for the digestive process.
Gallbladder
Helps the liver and serves as a kind of container for the processing of bile. At the same time it removes excess water from bile, thereby forming a concentration that is suitable for the digestive process.
Studying human anatomy, it is important to know and understand that the successful functioning of each of the organs and parts of the digestive system is possible with the positive work of all other interconnected parts.
Hepatic artery supplies the liver cells with arterial blood enriched with oxygen.Portal vein delivers venous blood to the liver from the abdominal organs. This blood contains the products of digestion of fats, proteins and carbohydrates from the stomach and intestines, as well as decomposition products of red blood cells from the spleen. After passing through the liver, this blood is collected by the hepatic veins and is directed through the inferior vena cava to the heart.
Carbohydrate exchange in the liver. Glucose, which is absorbed in the small intestine in the process of digestion, is converted into glycogen in the liver cells - the main storage carbohydrate, often called animal starch. Glycogen is deposited in the cells of the liver and muscles and serves as a source of glucose in case of its deficiency in the body. Simple sugars, such as galactose and fructose, are converted into glucose in the liver. In addition, in the cells of the liver, glucose can be synthesized from other organic compounds (the so-called gluconeogenesis process). Excess glucose is converted into fat and stored in fat cells in different parts of the body. The deposition of glycogen and its breakdown with the formation of glucose is regulated by pancreatic hormones insulin and glucagon. These processes play an important role in maintaining the constancy of glucose in the blood.
Fat exchange in the liver. Fatty acids from food are used in the liver to synthesize fats that are necessary for the body, including the most important components of cell membranes.
Protein exchange in the liver it consists in the breakdown and transformation of amino acids, the synthesis of plasma proteins, and also in the neutralization of ammonia formed during the breakdown of proteins. Ammonia in the liver is converted to urea and excreted in the urine. Other substances that are toxic to the body are neutralized in the liver.
Gallbladder adjacent to the lower surface of the right lobe of the liver. It has a pear shape, its length is about 10 cm, and the volume of 50 - 60 ml. Half of the bile produced by the liver enters the gallbladder and is then used as needed. Bile is secreted by hepatocytes and is a jelly-like substance with an alkaline reaction, a reddish-yellow color and a bitter taste with a specific odor. The color of bile is due to the content in it of the breakdown products of hemoglobin - bile pigments, and above all bilirubin. Bile also contains lecithin, cholesterol, bile salts and mucus. Bile acids play an important role in the digestion of fats: they contribute to their emulsification and absorption in the digestive tract. Under the influence of the hormone produced by the duodenum, the gallbladder contracts and bile is released through the common bile duct into the duodenum.
In order to support all the processes of vital activity, a person needs energy. We take it from food. To food turned into energy and gave the body all the necessary substances, there is the gastrointestinal tract. Here is the primary processing, digestion of food and disposal of its residues. Needless to say, any diseases of the gastrointestinal tract can greatly ruin a person’s life. It includes many organs and components, and therefore any violation can seriously affect the processes of digestion and seriously harm health. It is on the correctness and effectiveness of the processes of digestion that the supply of other organs and systems with the necessary substances depends, therefore, diseases of the gastrointestinal tract can lead to a variety of problems. In order to understand exactly what problems may arise, it is necessary to understand how the digestive system is made up, what components it consists of, and what disorders at what stage can cause diseases of the gastrointestinal tract.
Gastrointestinal tract: organs and structure
The gastrointestinal tract consists of several sections. Here the food is fully processed, saturating the body with useful substances. The first stage of digestion begins in the oral cavity. Here the food is subjected to primary machining. Teeth, tongue, salivary glands work together to prepare food for the stomach - grind and moisten it. This stage is very important, during which it is impossible to hurry. Popular wisdom says that you need to chew each piece 32 times - according to the number of teeth. This is a rational grain, because, the more thoroughly the food is crushed, the less stress on the digestive tract organs. From the mouth, food enters the esophagus, which is an intermediate stage between the mouth and the stomach. In the stomach, the main digestive process begins. While the food in the mouth was being prepared, gastric juice and all the necessary enzymes for its digestion had already been developed in the stomach. Contracted, the walls of the stomach grind and grind food, here begins the primary absorption and assimilation of nutrients. An empty stomach is about 0.5 liters in volume, but it can significantly stretch, increasing in size up to 8 times! The next stage of the gastrointestinal tract is the promotion of digested food in the small intestine. The small intestine has 3 divisions: duodenum, jejunum and ileum. All departments of the small intestine are covered with the smallest villi, which increase the absorption area of beneficial substances. This makes it the main suction organ of the digestive tract. Numerous studies confirm that in case of removal of a part of the small intestine, the body begins to experience a serious deficiency of beneficial substances. End the gastrointestinal tract colon. This includes the cecum, colon and rectum. In the large intestine, absorption of beneficial components is completed, excess fluid is absorbed, and fecal masses are formed. Through the rectum, they are brought out.
The gastrointestinal tract would not be able to perform its functions without auxiliary organs. Salivary glands, pancreas, liver - without them the process of digestion is impossible. And the actions of all organs are controlled by the brain, the endocrine and immune systems. As you can see, the process of digestion is incredibly complex, many organs are involved in it. Each stage is important and necessary, so any violation will affect the state of the whole organism.
Diseases of the gastrointestinal tract
Many diseases of the gastrointestinal tract are caused by impaired functioning of the immune system, which cannot cope with the number of harmful factors with which it occurs daily. And if a person has a genetic predisposition, multiplied by an unhealthy diet, abuse of tobacco and alcohol, then diseases of the gastrointestinal tract will not take long to wait. Consider the most frequent diseases of the digestive system.
Stomatitis is a disease that affects the mucous membrane of the mouth. It can be very unpleasant. As a result, the ability to chew food well decreases, which ultimately adversely affects the work of the stomach. The cause of stomatitis is weak immunity.
Esophagitis - occurs when the mucous membrane of the esophagus is inflamed. This can be caused by alcohol, excessively coarse, poorly chewed food, burns. Such diseases of the gastrointestinal tract, as esophagitis, cause quite severe pain and discomfort. There may be a burning sensation, vomiting, sometimes even with an admixture of blood.
Heartburn suffers a huge number of people. This condition is associated with an increase in gastric acidity. When part of it rises into the esophagus, there is a burning sensation.
Chronic gastritis is the most common gastrointestinal disease. Previously, it was believed that gastritis is a disease of students and people with a furious rhythm of life who eat irregularly and incorrectly. Today, it is absolutely certain that the vast majority of gastritis is caused by the bacterium Helicobacter pylori. Helicobacter pylori infection is one of the most common in the world and speaks eloquently about how miserable is the state of the immune system in most people. Chronic gastritis is an inflammation of the gastric mucosa. In fact, this is a disease that can have very serious consequences. First, the absorption of various beneficial substances is disturbed, for example, vitamin B12. A deficiency of this vitamin leads to the development of anemia. If you do not treat gastritis, it can develop an atrophic form, which is considered to be a precancerous condition.
Chronic duodenitis and chronic colitis are inflammations of the mucous membranes of the duodenum and large intestine, respectively.
This is not all diseases of the gastrointestinal tract. They are much more, among them there are very dangerous, such as peptic ulcer or pancreatitis. Of course, the ideal option is prevention, which will help prevent gastrointestinal diseases. But how to act if the disease is already diagnosed?
Treatment of diseases of the digestive tract and transfer factor
As we have said, the vast majority of diseases, including gastrointestinal diseases, cause disruption of the immune system. Enemy unicellular organisms, autoimmune processes, infections - all this occurs if the immune cells stop working as they are prescribed. Today, doctors and patients have at their disposal a unique drug that effectively treats gastrointestinal diseases and many other ailments. The immunomodulator Transfer Factor is a concentrate of compounds - long chains of amino acids that in the body of all mammals performs one function - the accumulation and transmission of information from the mother to her children. Receiving this information, immune cells are trained, trained and begin to clearly understand how they should act in order for the body to be healthy and protected. If you are worried about any diseases of the gastrointestinal tract, take Transfer Factor as an independent means or in the course of complex therapy to achieve the best treatment results.
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