The science of the geneticist found independence a little more than 100 years ago and began with studying hybrid life forms. In the center of consideration of modern genetics there are two fundamental properties of living organisms – heredity and variability. The methods used by scientists-geneticists allow to answer the important questions directly related to evolution of living organisms.
Genetics and heredity
In genetics understand universal ability of living organisms to transfer to posterity information on some essential signs and features of development as heredity. The heredity allows types of living organisms during very long periods of time to remain rather invariable. It is expression of continuity of generations.
All organisms can be grouped in system units, being distributed by types, childbirth and families. Such system nature of life on the planet became possible exactly thanks to heredity. This property gives the chance to keep characteristic features of similarity and distinction in the separate groups allocated within systematization.
One of functions of heredity consists in maintaining some signs passing through series of the generations replacing each other. Other function consists in ensuring nature of a metabolism, events in development of organisms and in providing the necessary type of development. Formation of a living organism goes through a number of the certain stages replacing each other in the accurate sequence. Such development programs also fall within the genetics sphere of interest.
Variability as genetics subject
Other subject of studying genetics – variability. This property reflects unstable maintaining signs which are descended from generation to generation. The reason of variability consists in change and combination of genes. These processes go during individual development of organisms. After heredity the variability is considered the second most important factor defining the course of evolution of life on Earth. Studying heredity of genetics is conducted, considering different levels of the organization of life. At the same time the analysis begins at the chromosomal and cellular level, gradually rising to organisms and the whole populations. The main method used at the same time is called the genetic analysis, including including elements of mathematical statistics. The variability of genes which finds manifestation at individual development of living organisms, is studied within a division of science, called ontogenetiky. The arsenal of methods is rather wide here, it includes the analysis of immunological reactions, change of fabrics and even cellular kernels. The modern genetics is armed with the effective tools allowing to study the properties of organisms described above defining evolution of vital forms.