Digestion is a fundamental part of human survival. Through this process people can replace nutrients in food within our body with other beneficial substances to keep us alive. But this does not happen only in people, there are many animals and plants that perform this function in order to survive.
There are two types of organisms that use various functions to feed and obtain energy. There are heterotrophic organisms, which will depend on being supplied with raw materials in order to maintain, grow and function. Autotrophic organisms (these are plants and photosynthetic organisms) will capture their energy through light, which will transform it into chemical energy.
What is digestion in people?
As the main theory, digestion is the transformation of food by hydrolosis, which will become small substances called nutrients. These substances will pass through the plasma membrane by a chemical reaction where it will be helped by enzymes. This process occurs mainly in the stomach, although many others are the organs that are part of the digestive tract.
basic organs for this digestion to occur are: the mouth, tongue, pharynx, esophagus, stomach, liver, pancreas, small and large intestine, rectum and anus.
In this transformation of food into substances, digestion is responsible for separating nutrients from toxins and residual elements. Then the body will be responsible for distributing these nutrients throughout the body and thus will be transformed into energy, something vital for subsistence. Toxins and residues which are not favourable shall be expelled.
Why is digestion important?
Because it is vital to our development and survival. With the intake of alimetos we are ingesting nutrients such as proteins, vitamins, fats, carbohydrates, minerals and water. They are essential components to survive, grow repair our body and have energy.
Step by step on digestion:
Digestion begins in the mouth: we introduce food into the mouth and perform a mechanical action that consists in chewing and decomposing food with the help of molars and salivary glands. There is what is called the bolus that with the action of swallowing will pass through the pharynx and from there into the esophagus.
In the esophagus the food bolus will be pushed into the stomach thanks to a few movements (the perisaltics), this is where the main step of digestion will occur.
In the stomach is where this activity occurs. Muscle movements will secrete gastric juices that will cause the bolus to fall apart and that is when it transforms it into chyme.
digestive glands are involved in this process of secreting enzymes: the liver and pancreas, which will help break down food.
At this stage, chyme, bile and digestive juices reach the small intestine and that is when transformation into nutrientsoccurs. This is when we can talk about chemical digestion, and that is when all these elements are doing their process so that the chyme breaks all intermolecular bonds.
It is the final part of digestion and that is where the large intestine participates. It is a process where toxins and residues that the body does not need will be removed. It is everything that has not been absorbed into the small intestine and has become a nutrient. These wastes are transformed into feces, run through the rectum and are expelled through the anus. This is when we talk about evacuation or defecation.