Sexual reproduction means that there is a male and female needed from a species to reproduce, e.g. humans, but this doesn't mean that asexual reproduction is bad either, asexual reproduction means that there is only one needed from each species, e.g. amoeba, thus saving energy and time.
However, there are some disadvantages of Sexual and asexual reproduction;
Sexual reproduction: More time and energy wasted, Harder to reproduce as you need to find another plant/animal.
Asexual reproduction: Could be wiped out because of a disease, as all the copies are identical. Cannot evolve. (see below)
Sexual Reproduction: Not all the 'copies' are identical, and therefore not so easy to wipe out because of a disease. As said above, not all the 'copies' are identical, if a species is varied it is more likely to be able to adapt to any changes in its surroundings, this leads to evolution.
Asexual reproduction: Offspring can be produced quickly.
Therefore, many people agree on that Sexual reproduction is better and more helpful, as Sexual reproducers will not be wiped out as easily.