Digestive system: anatomy, parts and function.
An overview of the parts of the digestive system and how it processes food.
Contrary to what many people believe, the digestive process does not just involve mixing food with the gastric acids in the stomach.
Both chemical and physical actions take place, starting in the mouth with ingestion and ending at the end of the digestive tract with egestion.
In this article we will talk about the digestive system, what organs it is made up of and which ones.The digestive system, what organs conform it and what functions each one of them exert.
The digestive system
In essence, this system is formed by all the organs that are involved in the process of digestion, which consists of transforming food into nutrients that can be used by the body so that it can maintain its physiological functions.
Its main function is to extract the nutrients that are present in the food by the action of enzymes and processes through the action of enzymes and physical processes that transform food into smaller elements. Once this has been done, the nutrients are absorbed and incorporated into the bloodstream, through which they travel throughout the body to reach the cells. Inside the cells, metabolic reactions take place that provide energy and substances to maintain the cellular structure.
In addition to nourishing at the cellular level, the digestive system is responsible for getting rid of substances that are not beneficial to the body.The feces will be eliminated from the body, whether they are non-useful substances or toxins and pathogens. These elements are the ones that will compose the feces, which will be eliminated through digestion.
Below we explain all the parts that make up this system, in addition to presenting them in the order in which digestion occurs and which are its fundamental functions during this process.
Digestion: the path of food through our interior.
This is the path that food takes as it passes through the nervous system.
The mouth is the entrance of food into our body and the place where the first phase of digestion takes place. the place where the first phase of digestion takes place: ingestion..
Here the food is reduced by chewing, breaking it down by physical action and transforming it into smaller parts.
In addition, the mouth secretes saliva, a liquid containing enzymes that break down the starches in food. This is the first chemical reaction to which the food is subjected once it has been incorporated into the organism.
The tongue is responsible for pushing the food down the throat.. Before reaching the esophagus it is necessary to prevent the food from ending up in the wrong way and being introduced into the lungs. For this reason, the epiglottis, a structure located in the trachea, folds, closing the entrance to the Respiratory system and preventing choking.
Once food has been swallowed, it travels through the esophagus. This is a tube through which food is carried to the stomach.. For this, it is necessary the action of muscles, which perform movements called peristaltic.
3. Lower esophageal sphincter
This is the part that separates the esophagus from the stomach, being the entrance door to the stomach. In order for food to be introduced into the stomach, it is necessary for this sphincter to relax and allow it to pass through. it is necessary for this sphincter to relax and allow it to pass through the esophagus..
In addition to allowing food to enter the stomach, the lower esophageal sphincter prevents what has been introduced from going backwards, since if this were to happen, reflux or even vomiting would occur.
Perhaps many consider it to be the main part involved in digestion, although the two intestines, the liver and the pancreas are of great importance in this process.
The stomach is a sac in which food is mixed by the action of muscular movements with gastric acids, which break down the food.which break down the food.
Thus the food is reduced to much simpler elements than it was originally made of, allowing these nutrients to be easily absorbed in later stages of digestion.
When this action has been accomplished, the stomach empties, moving the digested food into the chyme, located in the small intestine.located in the small intestine.
This organ is in charge of producing juices much more powerful than saliva, with which carbohydrates, fats and proteins in food are broken down. By means of ducts, this juice is taken to the small intestine, where it will carry out the decomposition of carbohydrates, fats and proteins..
6. Liver and gallbladder
The liver produces bile, with which some fats and vitamins present in the food are digested.
Through specialized ducts, bile is transported to the gallbladder, where it is stored until it is needed by the small intestine when digestion is taking place.
When a person eats, the gallbladder is squeezed and releases the bile through ducts through ducts that carry it to the small intestine.
7. Small intestine
In this part, food that has already been digested in the stomach is mixed with juices from the pancreas and liver, in addition to mixing with its own intestinal juice.
The bacterial flora present in the intestine is in charge of producing enzymes specialized in the digestion of some carbohydrates. An unhealthy intestinal flora can be the origin of diarrhea and nutritional problems, resulting in problems of digestion.which in the long run lead to health problems. The muscles of this organ are responsible for moving food forward.
In the walls of the intestine there are small hairs which absorb the water and nutrients present in the food, which have been reduced by the action of digestive fluids facilitating this phase. These are introduced into the bloodstream.
What cannot be used, either because it is not useful for the organism or because it can become toxic for our body, is taken to the large intestine..
8. Large intestine and rectum
Here what could not be digested, residual liquids and dead cells are treated for later elimination. In the large intestine the water that remains in these residues is absorbed, causing them to harden, transforming them into feces.
By means of peristaltic movements these waste products are carried into the rectum.where they will be stored until they receive the signal to be defecated and fulfill the last function of the digestive system, egestion.
- Keeton, W. and Harvey, D. (2016). Human digestive system. Encyclopedia Britannica.
- Moore, K.L. (1992). Clinically Oriented Anatomy. Baltimore: Williams & Wilkins.
(Updated at Mar 28 / 2023)