Question

Give the respective scientific terms for studying
i. The mechanism by which variations are created and inherited
ii. The development of a new type of organisms from the existing ones

Answer 1

Hint:- Variation is the difference between the individuals within the same species. The difference occurs between individuals mainly because of a change in their DNA sequence. Variation for a long period leads to evolution. The evolution later will lead to the formation of new species.

Complete step-by-step solution:- The variation is important for the population because it helps individuals to adapt to the changing environment. It increases the chances of survival. Variation can also occur inside the Genus.
Types of variation: somatic variation: this occurs within the somatic cells. they can not be inherited.
Germinal variation: it occurs within the generative cells I.e. egg or sperm. They can be heritable.
Evolution is a change in the variation of characters of a species over some time for many generations. By studying the DNA of the individuals of each generation the evolution can be studied. Heredity is the process by which the allele or genes from the parent are transformed into the offspring.
Asexual reproduction produces the individuals which are. And there is no variation in the DNA. Hence it will not involve evolution. This is because asexual reproduction involves only one parent and there are no gametes involved and fertilization is absent.
In the case of sexual reproduction, two parents are involved so the genetic material is shared by both parents. And the offspring produced will be different than that of the parent. It provides variation and later leads to evolution.it involves the formation of gametes and fertilization.
1. The mechanism by which variations are created and inherited is sexual reproduction.
2. The development of a new type of organism from an existing one is called evolution.

Note:- Speciation: it is the term used when a new species is formed due to variation and in the course of evolution.
The variation can also be of two types- variation due to environmental factors.
Due to changes in the environment, climate variation may be formed. It may or may not be inherited from parent to offspring. It may be hereditary which is passed from parents to offspring. The environment does not affect this type of variation.