Structure of the Organism, Exchange of Substances in Organism

In our body there are many organs, each performing certain functions. The human skeleton and its muscles are the organs responsible for support and movement, the heart and blood vessels are organs that ensure the continuous movement of blood. The activity of all our organs is united by the nervous system, so they interact in a coordinated way in a living organism.

Our organs, like the organs of animals, consist of tissues, which in turn contain a huge number of different cells. The cell itself is so small that it can only be seen with a microscope. Basically, the cells have a body and a nucleus, most cells have one or more processes. The body of the cell consists of a special substance, with a very complex chemical composition - protoplasm.

A huge number of cells, united in a single system with one origin and the same structure, performing certain functions, together with a substance that is in between the cells, is called a tissue. There are epithelial, connective, muscle, nerve and other tissues. All of them differ from each other in their structure and function, which is assigned to each of them in the life of the organism. But they all have a common property-they regularly metabolize and energy.

Our life is such a way of existence of protein bodies, the main point in which is the continuous exchange of substances with their surrounding nature. In the living organism , all kinds of substances regularly come from the surrounding environments and substances that are already unnecessary to the body and harmful to the body are removed from the body. In animals and humans, when breathing, oxygen enters the body and vice versa, carbon dioxide is removed, nutrients necessary for life enter the food , and substances unnecessary to it through the kidneys, through the skin, through the intestine are released. Stopping such a metabolism will lead to the cessation of life, to death.

Throughout life in our body and during the hours of wakefulness and work, and at night in the arms of "Morpheus" there is not always visible, but continuous work. Every second the heart muscle is contracted, this ensures a constant movement of blood through our body. Approximately 18-20 times a minute the thorax squeezes and expands, squeezing the air outwards, then sucking it into the lungs. Every second our nervous system is active. Much mechanical work is done by the muscles. We know that any work is connected with energy consumption. Where does the energy, so necessary for the continuous work of muscles and organs, take?

This energy is released when the substances that are complicated by their chemical composition break up into simple substances. Such chemical transformations are called dissimilation, they continuously occur in the body. With them are closely related and constantly occur in our body and the processes of assimilation, that is, chemical transformations, which lead to the creation of complex in chemical structure of substances from simpler substances.

With dissimilation, so-called. Chemical energy is converted into thermal, electrical energy and mechanical energy, so necessary for our body, for the work of muscles and other organs, and for maintaining a constant t of the body. Assimilation processes accumulate potential energy.

Thus, the metabolism in our body is closely connected with the exchange of energy, that is, with the transition of one type of energy to another.

Most of our body, not counting water, is made up of proteins, carbohydrates and fats. These are substances that are complicated by their chemical composition, when they decay, energy is released. Carbohydrates, fats and proteins come into our body with food. Therefore, it can be argued that food and the natural vitamins contained in it are a source of energy.