The Biology Coach: Topic 2, Key Area 3a

Advantage of asexual reproduction

Metabolic costs are lower; rapid production of offspring; successful parental genomes remain intact

Disadvantage of asexual reproduction

Lack of variation in population to buffer against selection pressures

Disadvantage of sexual reproduction

High metabolic costs; only half the population can produce offspring; successful parental genomes are disrupted

Advantage of sexual reproduction

Generation of genetic variation

How does the Red Queen hypothesis apply to coevolution of parasites and hosts?

Host organisms that are being better able to resist and tolerate parasites have greater fitness; parasites better able to feed, reproduce and find new hosts have greater fitness

Environmental scenarios when asexual reproduction might be favoured

particular narrow and stable niches; when re-colonising disturbed habitats

Examples of asexually-reproducing prokarotes

Bacteria and archaea

How is variation still generated in asexually-reproducing prokaryotes?

Horizontal gene transfer.

Examples of asexually-reproducing eukaryotes

Plants that carry out vegetative propagation via bulbs, corms, tubers, stolons and rhizomes; Animals that use parthenogenesis.

Circumstances when parthenogenesis is more common

cooler climates and regions of low parasite density.