A nutrient it is that which nourishes, namely, which increases the substance of the animal or plant body. These are chemicals that come from outside the cell and that it requires in order to develop its vital functions. Nutrients are absorbed by the cell and transformed through a metabolic process of biosynthesis (known as anabolism) or by degradation, to obtain other molecules.
Among the various substances that make up food, nutrients are those that actively participate in metabolic reactions. The water, the oxygen and minerals are the basic nutrients that plants consume, while humans and animals eat plants and other animals.
The vitamins, proteins, lipids and carbohydrates are some of the substances that are part of the nutrients consumed by all living beings that do not have photosynthetic capacity (that is, they are not plants).
According to their function In metabolic reactions, nutrients can be classified into two large groups: essential nutrients (vital for the organism since it cannot synthesize them, but obtains them from the environment) and nonessential nutrients (They are not vital and, in certain cases, can be synthesized by precursor molecules).
Another classification of nutrients can be made according to the volume in which the cells consume them. The macronutrients are necessary in large daily amounts (such as protein) and form the basis of the diet. The micronutrientsInstead, they are required in small quantities and usually act as regulators of energy processes.
The path that substances essential for life travel, both through the physical and biological environments, is known as nutrient cycle and is considered a fundamental concept for the ecology. Among the essential cycles are those of carbon, oxygen, nitrogen, and water. There are many more vitally important compounds and elements, albeit in considerably smaller amounts.
Two of the most significant cycles for the life of the Planet are detailed below:
* carbon cycle: these are the different stages in which the ecosystem of the Earth uses carbon. Basically, it begins at the moment in which the plants take advantage of the carbon dioxide existing in the atmosphere, or present in the water in a dissolved state, through the process of photosynthesis. A percentage of this carbon is integrated into plant tissues as carbohydrates, proteins and fats; the rest is returned to its place of origin through breathing. In this way, herbivorous animals consume it while feeding, to later reorganize and degrade its compounds. One part is released through respiration, and another is stored in the tissues, which will later be ingested by carnivorous animals. In all cases, carbon is broken down and released as carbon dioxide, which is used by plants to restart life. cycle;
* water cycle: all the aquatic portions of the Earth are constantly modified, but the amount is always the same. First, the ocean surface evaporates and begins to rise. During its upward journey, a cooling of the vapor occurs, which turns it into Water condensed, which results in the formation of clouds. Depending on the temperature of the atmosphere, the water precipitates in the form of snow or rain, thus returning to the planet. Once on the surface, a part will be consumed by living beings, while the rest will be distributed between the soil and bodies of water, such as rivers and oceans.