In the etymology of the word nutrition it comes from the Latin that means "to give food, to maintain, to supply with what it needs to act ", with its lexical components that are "nutrire" means "to nourish" and the prefix "cion" means " action and effect ”. The nutrition is the main thing that makes initiated the knowledge by which the body takes nutrients from food through a series ofUnconscious phenomena such as nutrition, the impregnation of the nutritive substances of the food into the blood through the digestive tract and the digestion of the same by the cells of the organisms, maintaining the homeostatic balance of the organisms at the molecular and macrosystemic level.
The nutrition is the biological knowledge in which bodies digest food and liquids for operation, growth and maintenance of vital performance. It is also the study of the link between food and health, especially when dieting.
The development of macrosystemics that is linked to implementation, such as digestion, which is the process of variation of the food that is ingested, in the elements that are easier to impregnate.
In metabolism they are biochemical reactions and physical-chemical processes that happen in a cell and in the organism in which the interrelated process are the basis of life on a molecular scale that are what allow the different activities of the microscopic unit of living beings, in which they can grow, reproduce, among others.
The excretion, the process is physiological, which allows the body remove items from waste harmful to the body and thus to maintain the balance of the composition of the blood and other organic fluids.
