Describe how a living organism develops.

Variability of living organisms. The property of variability of living organisms is closely related to heredity. With variability, hereditary inclinations change – genes, the basis of heredity. If heredity did not change, then living organisms would not be able to adapt to changing environmental conditions. In organisms, new signs and properties of gene structure appear. Variability creates material for natural selection, that is, the organism adapts to specific environmental conditions, which leads to the emergence of new species.
Growth and development of living organisms. One of the properties characteristic of all living organisms is growth and development. In the process of the growth of the organism, the mass of individual organs increases due to the increase in the number of cells, and young individuals gradually become adults. Development is understood as an irreversible, directed, regular change in objects of animate and inanimate nature. As a result of development, new properties appear, the composition and structure of living organisms and inanimate nature change. The individual development of living organisms is called ontogeny, and their historical development is called phylogeny. During ontogenesis, the individual properties of organisms gradually and consistently manifest themselves. The development of living organisms is accompanied by growth. Phylogenetic development of living organisms is the irreversible and directed development of living nature, accompanied by the formation of new species and the complication of life.