what is the source of genetic variation in asexually reproducing organisms
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Asexual reproduction is the creation of offspring from one parent. ... There is usually no variation from generation to generation in a species population that relies on asexual reproduction. One way for an asexually reproducing species to get some diversity is through mutations at the DNA level.
In asexual organisms variation can occur from a variety of sources - mutations, homologous recombination and plasmid transfer. Mutations occur at a rate of roughly one base per million, meaning you would get between 0.1 and 10 in bacteria due to the size of their genomes. Depending on the actual mutation these can show anything from no changes to a significant effect. Homologous recombination occurs when reproducing a chromosome, it allows the crossing over of sections so a mutation can end up in one offspring as opposed to the other, changing the effects. Finally plasmid transfer allos exchange of small DNA structures between bacteria, hurrying along factors such as antibiotic resistance. In sexually reproducing organisms there are mutations and the crossing of gametes. The mutations occur in a near identical way to in asexual reproducing organisms as long as they occur in germline cells. Cells in the rest of the organism do not pass on to offspring so have no effect. Gametes are produced from these germline cells and contain half the genetic information of the host. By the crossing of gametes from to parents there is a wide range of diversity available - look up Mendilian inheritance for a greater background on this. The effects of natural selection apply to both groups as the changes effect organsisms and if beneficial they become dominant in a population. As to which has the greatest variation - that's a difficult one. In theory there is more change per generation in sexually reproducing organisms due to the gametes. However, asexually reproducing organisms reproduce much, much faster and so variation can occur more rapidly. For example the variation in the HIV viral propulation in an individual after 5 years is an immense diversity, higher than all the diversity that the human population has managed in thousands of years.
In asexual organisms variation can occur from a variety of sources - mutations, homologous recombination and plasmid transfer. Mutations occur at a rate of roughly one base per million, meaning you would get between 0.1 and 10 in bacteria due to the size of their genomes. Depending on the actual mutation these can show anything from no changes to a significant effect. Homologous recombination occurs when reproducing a chromosome, it allows the crossing over of sections so a mutation can end up in one offspring as opposed to the other, changing the effects. Finally plasmid transfer allos exchange of small DNA structures between bacteria, hurrying along factors such as antibiotic resistance. In sexually reproducing organisms there are mutations and the crossing of gametes. The mutations occur in a near identical way to in asexual reproducing organisms as long as they occur in germline cells. Cells in the rest of the organism do not pass on to offspring so have no effect. Gametes are produced from these germline cells and contain half the genetic information of the host. By the crossing of gametes from to parents there is a wide range of diversity available - look up Mendilian inheritance for a greater background on this. The effects of natural selection apply to both groups as the changes effect organsisms and if beneficial they become dominant in a population. As to which has the greatest variation - that's a difficult one. In theory there is more change per generation in sexually reproducing organisms due to the gametes. However, asexually reproducing organisms reproduce much, much faster and so variation can occur more rapidly. For example the variation in the HIV viral propulation in an individual after 5 years is an immense diversity, higher than all the diversity that the human population has managed in thousands of years.
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The only source of variations in asexually reproducing organisms is the mutation. Mutation refers to the sudden change in dna.hence variations eill occur with changes in dna
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