Question

Higher organisms have resorted to sexual reproduction in spite of their complexity. Why?

Answer 1

Hint: Reproduction is a biological process by which new individuals are produced from their parents. Reproduction is essential for the continuation of life on this Earth.

Complete Answer:
Sexual reproduction: Sexual reproduction involves two parents of different sexes I.e. male and female. It is a process in which new organisms are formed by combining the genetic information from two individuals of different sexes i.e male and female.
- The genetic information is carried by the nucleus of the sex cells or gametes.
- In males, these gametes are called sperms while in females these gametes are called ova or eggs.
- During sexual reproduction, the two gametes i.e. sperm and ova join together and fuse by a process called fertilization to form a diploid structure called Zygote.
- Zygote divides further and forms a spherical ball of cells called Embryo. Zygote contains 46 chromosomes – 23 from the mother and 23 from the father.
- The combination of both of these chromosomes produce offspring that are similar to both of its parents i.e mother and father but the offspring is not identical to either of the parents.
- Higher organisms have resorted to sexual reproduction in spite of their complexity because sexual reproduction helps in introducing variations in the progenies due to the combination of DNA from two different parents. These variations allow the survival of offspring in a changed environment. Variations also lead to the evolution of new species.

Note: Apart from the sexual reproduction, there is another mode of reproduction i.e. asexual reproduction. In asexual reproduction only one parent get involved. The offsprings arise from the asexual reproduction are the clone or exact copies of their parents. Example – in Amoeba, Hydra, etc.