– By origin, spontaneous and induced mutations are distinguished. Spontaneous mutations occur spontaneously throughout the life of an organism in normal environmental conditions. Induced mutations are those mutations artificially induced by mutagenic factors under experimental conditions. Induced mutations occur many times more often than spontaneous ones.
– Somatic and generative mutations are distinguished by the type of mutated cells. Somatic mutations occur in somatic cells. They can occur in the individual and be transmitted to offspring during vegetative propagation. Generative mutations occur in germ cells and are transmitted to offspring through sexual reproduction.
– According to the influence on the viability and fecundity of individuals, lethal, semi-lethal, neutral and useful mutations are distinguished. Lethal mutations lead to the death of the body (for example, in humans, the absence of X chromosomes in the set causes fetal death in the third month of embryonic development). Semi-lethal mutations reduce the viability of mutants (hemophilia, a congenital form of diabetes, etc.). Neutral mutations do not significantly affect the viability and fecundity of individuals (appearance of freckles). Useful mutations increase the adaptability of organisms to environmental conditions (mutations causing immunity to certain pathogens – HIV, malarial plasmodium, etc.)
Remember: The process of learning a person lasts a lifetime. The value of the same knowledge for different people may be different, it is determined by their individual characteristics and needs. Therefore, knowledge is always needed at any age and position.