Even a cursory review of the methods of reproduction of different groups of organisms shows that the evolution of asexual reproduction gives way to s

Advantages of sexual reproduction [propagation, Benefits]

Even a cursory review of the methods of reproduction of different groups of organisms shows that the evolution of asexual reproduction gives way to sexual. Indeed, asexual reproduction — is a mandatory attribute of single-celled organisms, fungi, algae and spore plants, as well as of the most primitive multicellular animals. Seed plants are already losing the ability to reproduce via spores, and many of them are not even capable of vegetative reproduction. Higher animals generally reproduce only sexually. What accounts for benefits of sexual reproduction? Why the most advanced organisms prefer to reproduce via gametes and not via body parts or spores?

In contrast to the asexual reproduction, which, in fact, is the process of copying the source of the maternal organism in a number of generations, in the process of sexual reproduction each individual is unique. This is due to the fact that during the formation of haploid cells (spores of plants or animals gametes) genetic material of parental individuals recombines.

As a result, despite the fact that the spores or gametes form in one body, and some even originate from common original parent cells, they differ from each other because each carry their own genetic information. In addition, parents of different gametes merging with each other form in a zygote completely new genetic combinations. The result is that in the process of sexual reproduction, each individual gets “own face” — own set of genes which determine the uniqueness of its structure (diagram 7) and functions. This means that each organism has specific biological properties. Some individuals seem to tolerate the heat, the second — cold, others are able to multiply rapidly, fourth are resistant to diseases. As a result, there are always resistant to adverse factors at sharp warming, extremely harsh winters or epidemics. They survive and give rise to new generations. When the favorable conditions occur, appear new leaders, whose value lies in other capacities, such as rapid reproduction.

Diagram 7. The uniqueness of each human person — is the result of an individual set of genes, which is formed as a result of sexual reproduction

In the asexual reproduction each organism reproduces without any participation of individuals of its species; with sexual reproduction all organisms belonging to the same species, potentially linked with “bonds of marriage”. Hereditary changes occurring in the genetic apparatus and allowing the body to have certain advantages in comparison with other individuals of its species, not only increase its chances of survival, but also make it possible to leave more offspring with such advantageous properties. Taken from http://worldofschool.org

This key position in modern biology applies to organisms that reproduce both asexually and sexually. However, the exchange of useful “acquisitions” cannot be done by asexual organisms. But it's easy done by the creatures that reproduce sexually. Therefore, if the genetic characteristics of one animal, allowing it, for example to endure harsh winters, in descendants merge with other, equally useful, such as tolerability of helminth infections, then it clearly have more chances to survive and leave offspring, than in ancestors, endowed with only one of these positive properties. If we add to this that in sexual reproduction the number of potential offspring is much greater than in asexual such positive changes in the number of generations will accumulate even faster. This means that sexual reproduction provides more material for evolution than asexual. It is obvious that in evolution the sexual reproduction has all the advantages over asexual and therefore the most highly organized, evolutionarily advanced organisms at some point refused to asexual reproduction.

The benefits of sexual reproduction over asexual are due to the fact that the offspring receives a variety of properties, which significantly increase the stability of species to changing and adverse conditions of environment and gives a lot more raw material for evolution.

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  • What are the advantages of sexual reproduction over asexual?