Molecular genetic level. No matter how difficult any living system is organized, it is based on the interaction of biological macromolecules: nucleic acids, proteins, carbohydrates, as well as other organic and inorganic substances.
Cell level. A cell is a structurally functional unit of all living things. The existence of a cell underlies the reproduction, growth and development of living organisms.
Fabric level. Tissue is a combination of cells and intercellular substance, united by a common origin, structure and function. In animal organisms, four main types of tissue are distinguished: epithelial, connective, muscle and nervous. In plants, educational, integumentary, conductive, mechanical, basic and excretory (secretory) tissues are distinguished.
Organ level. An organ is a separate part of an organism that has a certain shape, structure, location and performs a specific function. An organ, as a rule, is formed by several tissues, among which one (two) predominates.
Organizational (ontogenetic) level. An organism is a holistic single-celled or multicellular living system,
capable of independent existence. A multicellular organism is formed, as a rule, by a combination of tissues and organs.
Population and species level. Population – a collection of individuals of one species, for a long time living in a certain territory, inside which random crossing is carried out to one degree or another and there are no significant internal isolation barriers; it is partially or completely isolated from other populations of this species.
Biogeocenotic (ecosystem) level. Biogeocenosis is a historically established set of organisms of different species that interacts with all factors of their environment. In biogeocenoses, the circulation of substances and energy is carried out.
Biosphere (global) level. The biosphere is a biological system of the highest rank, covering all phenomena of life in the atmosphere, hydrosphere and lithosphere. The biosphere combines all biogeocenoses (ecosystems) into a single complex. All material and energy cycles associated with the vital activity of all living organisms that live on Earth take place in it.