Answer: Sexual reproduction involves two parents and the joining of male and female gametes during fertilisation. The offspring inherit a mixture of genes from both parents, so are different to each other and their parents. In asexual reproduction there is only one parent. The offspring are clones of the parent and each other, so:
Disadvantages of Asexual Reproduction: There will be a lack of genetic variation because the daughter offspring look exactly and have the same genetic material as the parent.A negative mutation can make an asexually reproduced organisms susceptible to disease and can destroy large numbers of offspring.They're less likely to adapt in a changing environment.In Asexual Reproduction every member is identical so each and everyone is susceptible to the same disease whereas in sexually produced offspring they are all unique genotypes so some might have a resistance to some diseases and others might not so the population would sustain.A disadvantage is due to no competition for breeding and each individual is capable of breeding,there won't be enough resources because their population doubles after every reproduction cycle.
Disandvantages of Sexual Reproduction: Requires more energy to sexually reproduce than asexually because they rely on the presence of animals or wind to pollinate. In the end only a few seeds will germinate. Plants have to be visually appealing to attract insects to the flower. Genetic "errors" happen more frequently because meiosis is more complex than mitosis. Organisms are not as well as adapted to their environment as their parents.