Reproduction is essentially a phenomenon that is not for survival of individual but for the stability of a species. Justify. Reproduction is not essential for survival of the individual.
Survival of the individual depends upon input of nutrients and energy and elimination of wastes. Reproduction has ho role in these. It is, however,
essential for the stability and survival of the species. Reproduction takes part in
(a) Perpetuation of Species: Perpetuation or continuation of species.
(b) Replacement: Replacement of dead individuals and maintaining the organisation in population.
(c) Population Characteristics:
- Education: There is an inverse ratio between education and population growth.
- Population Education: It is imparting knowledge to public about the effects of excessive population, advantages of small families and means to achieve it.
- Marriageable Age: Number of births is reduced if young persons marry late. Gainful employment and higher social status of women also reduce birth rate.
(d) Variations:
Variations are differences found in morphological, physiological and other traits of individuals belonging to the same organism, race or family. They develop due to
- Faulty DNA replication
- Crossing over
- Chance separation of chromosomes during meiosis and chance combination during fertilization. Variations are highly important.
(e) Absence of Variations: Due to absence of variations, asexually reproduced organisms are unable to adapt themselves to changes in the environment.