Reproduction is the action and result of reproducing something that already exists or has existed, it means “to produce again” or “to produce again”. For example; in our daily life we can reproduce a sound, song, video, film, image, text, presentations, as well as a work of art, architectural object, clothing, among others.
In biological terms, reproduction is one of the characteristics of living matter. Through it, living beings multiply their structures and give rise to other beings identical or very similar to them. This phenomenon can be found at different levels of the biological world, from the molecular, with the duplication of DNA, to the cellular and the individual himself.
Given the limited duration of life, in all living beings, reproduction is a basic function that ensures that the species remains or lasts through time.
The formation of new individuals depends on the degree of specialization of each organism. Thus, the reproduction of organisms can be asexual or sexual. In the first, a single parent participates, and occurs mainly in simple unicellular or multicellular animals and in plants.
Asexual reproduction, also known as agamia , is one that any part of the body can give rise to a new individual, without requiring the intervention of specialized cells (there is no meiosis). The individual thus generated is identical to his progenitor. There is this reproduction in different classes: bipartition, budding, sporulation or multiple division, fragmentation and regeneration.
In sexual reproduction, the union of two specialized cells called sex cells or gametes is required to form a new individual. Each gamete has its own characteristics and allows differentiating the sexes (male and female) in organisms that have this type of reproduction.
The sexes that can be separated are known as unisexual or dioecious organisms , when they are together in the same individual they are hermaphroditic or monoecious organisms . This last phenomenon occurs in some animals (earthworms, snails, etc.) and in a large number of vegetables. In hermaphrodites, female and male activities can be simultaneous or successive.
The formation of gametes in the sexual organs occurs in the process called gametogenesis , in successive phases of proliferation, growth and maturation , starting from spermatogonia and oogonia.
The fusion of the two gametes to form an egg cell or zygote constitutes fertilization. When an egg develops without the intervention of the male gamete, it is called parthenogenesis .
