In essence, this system is made up of all the organs that are involved in the digestion process, 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 food 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 will travel throughout the body to reach the cells. Inside cells, metabolic reactions occur that provide energy and substances to maintain cellular structure.
In addition to nourishing at a cellular level, the digestive system It is responsible for getting rid of those substances that are not beneficial for the body , whether they are non-useful substances or toxic and pathogenic ones. These elements are what will make up the feces, which will be eliminated through egestion.
Below we explain all the parts that make up this system, in addition to presenting them in the order in which digestion occurs and what their fundamental functions are during this process.
Digestion: the path of food through us
This is the route that food takes to pass through the nervous system.
1. Mouth
The mouth is the gateway for food to enter our body and the place where the first phase of digestion occurs: ingestion
Here food is reduced through chewing, breaking it down through physical action and transforming it into smaller parts.
In addition to this, saliva is secreted in the mouth, a liquid that contains enzymes that break down the starches in food. This is the first chemical reaction to which food is subjected once it has been incorporated into the body.
The tongue is responsible for pushing food into the throat Before reaching the esophagus, it is necessary to prevent food from going down the wrong route and being introduced into the lungs. For this reason, the epiglottis, a structure found in the trachea, folds, closing the entrance to the respiratory system and preventing choking.
2. Esophagus
Once food has been swallowed, it travels through the esophagus. It is a tube through which food is carried to the stomach To do this, the action of muscles is necessary, which perform movements called peristaltics.
3. Lower esophageal sphincter
This is the part that separates the esophagus from the stomach, being the entrance door to the latter. So that food can be introduced into the stomach It is necessary for this sphincter to relax and let it pass
In addition to allowing food to enter the stomach, the lower esophageal sphincter prevents what has been introduced from returning back, since if this occurred, reflux or even vomiting would occur.
4. Stomach
Perhaps many consider it 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 food.
Thus, the food is reduced to much simpler elements than what it was originally made of, allowing these nutrients to be easily absorbed in later phases of digestion.
When this action has been carried out, the stomach is emptied, moving digested food into the chyme located in the small intestine.
5. Pancreas
This organ is responsible for producing juices that are much more powerful than saliva, with which carbohydrates, fats and proteins in food are broken down. Through some ducts, This juice is taken to the small intestine, where it will be decomposed
6. Liver and gallbladder
The liver produces bile, with which some fats and vitamins present in food are digested.
Through specialized ducts, bile is transported to the gallbladder, where it is stored until it is needed by the small intestine during digestion.
When a person eats, the gallbladder is squeezed and releases bile through ducts that take it to the small intestine.
7. Small intestine
In this part, the foods that were already digested in the stomach are mixed with juices from the pancreas and liver, in addition to mixing them with your own intestinal juice.
The bacterial flora present in the intestine is responsible for producing enzymes specialized in the digestion of some carbohydrates. A sick intestinal flora can be the source of diarrhea and nutrition problems , which translate into health problems in the long run. The muscles of this organ are responsible for making the food move forward.
On 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 body or because it can become toxic to our body, is carried to the large intestine
8. Large and straight intestine
Here what has not been digested, residual liquids and dead cells, is treated for subsequent elimination. In the large intestine, the water remaining in these waste is absorbed, causing it to harden and become feces.
Through peristaltic movements these waste products are carried towards 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.
