What is a gene?
It is thanks to the genes that any living organism on our planet inherits the attributes of parents, thus continuing the uniformity of its kind. The gene information is transmitted to us from the father and mother in the form of DNA molecules, which contain the genes - separate properties and characteristics of the future organism. From our article you will learn about what a gene is, what its properties are and why nature needs it.
Gene: definition and purpose
A gene is defined as a structural and functional unit of heredity of living organisms. Genes are a pledge of our “similarity” to our parents. Each gene contains a sample of one protein molecule and one RNA molecule (ribonucleic acid is part of a common DNA code). This sample and transmits the cell development plan in all systems of the future organism. Any gene is designed to encode information. Let's take a closer look at the structural features of this particle.
Gene structure and its features
On each of the genes there are sections of molecules that are responsible for one or another part of the code. Their various variations give the body a program for coding and reading its properties.In this case, it is appropriate to make an analogy with a computer processor, in which all tasks are performed at the level of education and code conversion.
In addition, it was found that one gene consists of multiple pairs of nucleotides. Depending on the task and the complexity of the information transmitted, the number of pairs varies and can range from several hundred to several thousand.
Properties of genes and their significance
- Discreteness The word itself denotes something that has a discontinuous structure of the structure. With respect to genes, discreteness is understood as a property that allows a molecule to share information without confusing it with information from another molecule. Each group of nucleotide pairs is separated from another similar group. This gives us a clear and unambiguous inheritance of certain signs.
- Stability. This property allows the gene to maintain its structure. Thus, the same gene is transmitted from generation to generation, copying itself when a new organism is born. This property allows you to save the principle of species similarity.
- Lability. In contrast to the previous property, gene lability works - the ability to mutate.This property is due to the laws of evolution and natural selection. Each organism, as it lives, receives a certain experience of living in the conditions established in nature. This information also enters the genes that incorporate it into their structure, thus adapting the entire future genus.
- Multiple allelism. This property gives intraspecific diversity. So, thanks to groups of genes with different sets of characteristics, the rabbit has different colors (white, Himalayan, albino). Different types of human blood are also caused by multiple allelism. By and large, this property allows you to expand the palette of tools adaptability of the form.
- Specificity. It is known that the number of genes in a single DNA molecule is enormous. This is due to the fact that each of the genes encodes its specific trait of the future organism. This, in fact, expresses the property of specificity. One gene - one sign.
- Pleiotropy. This property is responsible for transferring mutations in one gene to others. Moreover, the mutation affects not only the genes themselves, but also those signs that can be encoded. For example, the color of bird feathers may be susceptible to mutations in the structure of wing cells.Thus, the cell structure genes also affect the results of the resulting color of the wings.
- Expressiveness. This property reflects the degree of expression of a gene in one trait. It is necessary for flexibility in the transmission of hereditary information.
- Penetrance is an indicator of how often a trait occurs in the phenotype (developmental stage within a single organism).
- Amplification. It is responsible for the degree of increase in the number of copies of one gene. As a rule, this property manifests itself in response to human selection actions (when creating new species). In nature, amplification is rare.