Sexual reproduction is an early
evolutionary modernization after the appearance of eukaryotic cells. During
sexual reproduction, the genetic material of two individuals is put together to
produce genetically-diverse offspring that is not the same from their parents. Actually
there are more eukaryotes reproduce sexually is the proof of its evolutionary
success. Most of the animals, it is actually the only way of reproduction. The
genetic diversity of sexually-produced offspring is thought to produced species
a better chance of surviving in a changing or unpredictable environment.
The variation that sexual
reproduction make among offspring is very important to reproduction of the
population and the survival .
In sexual reproduction, different
mutations are continually reshuffled from one generation to the next when
different parents combine their unique genomes; this results in an increase of
genetic diversity.
<span>On average, a sexually-reproducing population
will leave more offspring than an otherwise similar asexually-reproducing
population.</span>
Meiosis is the process of cell division by which involving gametes. Cell division is just the same for sperm and egg cells, but they have distinguishable descriptions and labels in the process. Spermatogenesis is for the males’ sperm cells and oogenesis is the process for females’ egg cells. The cell division of meiosis involves the two phases, respectively meiosis I and meiosis II. Meiosis I like mitosis is the cell division that produces diploid cells<span>. These diploid cells are cells that contain a complete pair of chromosomes which is 46. The result is two diploid cells after the first meiosis. To provide clear explanation, in contrast haploid cells only contain 23 chromosomes and are created after meiosis II which is 4 in number. </span>
All living organisms share several key characteristics or functions: order, sensitivity or response to the environment, reproduction, growth and development, regulation, homeostasis, and energy processing. When viewed together, these characteristics serve to define life