The universal principle "from simple to complex" is valid for all known levels of organization of matter and manifests itself at each of its steps in the form of a level of organization.
Every living organism is a mobile system open to interaction with the external environment. The main "building materials" of a living cell are proteins, lipids, carbohydrates, nucleic acids.
Levels of organization of multicellular organisms
The molecular level of organization of living matter is the simplest and is inherent in all living organisms, ranging from bacteria and protozoa. Chemical reactions that carry life-supporting functions take place on it, and hereditary programs embedded in nucleic acids are also implemented. Next is the cellular levelorganization of living matter - has slightly different properties. It is the cell that is the minimum structural unit of living matter, providing it with such fundamental functions as growth, development, and reproduction. Metabolic processes take place in the cells.
Levels of organization of multicellular organisms
Similar in structure and function, cells form four main types of tissues: connective, epithelial, nervous, and muscle. Several types of tissues, one or two of which play a more significant role, form an organ - a separate part of the body that has a given location and performs a certain set of functions. Organ systems are combined, creating a new level of organization of living matter - organismic; it is inherent mainly in multicellular living beings. Each organism is a stable system, relatively autonomous from the environment and able to adapt to its conditions. Due to the fact that living organisms belonging to the same species have a similar structure and functions, they are able to unite in populations, occupying certain territories, which are characterized by certain climatic features.
Being the simplest unit of the evolutionary process, the population ensures the exchange of genetic information, the course of the processes of heredity and variability. Biocenoses, which are associations of populations of various species, through interaction with oc
environment occupy the next level of organization of living matter. It is biogeocenosis that ensures the circulation of substances that exists in nature, as well as the maximum interaction of animate and inanimate nature.
The highest existing level of organization of living matter - biospheric - unites biogeocenoses. It has a single flow of energy, and also combines all of the above levels into a single whole. It is this level of organization of living matter that has the widest range of functions, which include maintaining the constancy of the external and internal structure of living nature, structuring and systematizing its main elements.
