Accumulation of Variation During Reproduction – CBSE Class10 Notes

Accumulation of Variation during reproduction is defined as a process in which new mutations are added to the population which further leads to an increase in genetic diversity which can be due to several factors such as migration, natural selection, genetic drift, and so on.

Accumulation of Variation is an inbuilt kind of tendency that lays a pathway for the evolution purpose. In sexually reproducing organisms changes of Variation are high whereas in asexually reproducing organisms the variation is limited.

Accumulation of Variation

Accumulation of Variation during reproduction refers to the process by which the genetic variation is increased in the population over time. There are mainly two modes of reproduction asexual reproduction and sexual reproduction. In asexual reproduction, the genetic makeup of a single parent is transferred to the offspring whereas in sexual reproduction there is an involvement of genes between both the parents. In asexual reproduction there not much variation in physical characteristics but in sexual reproduction there is a lot of variation among the organisms.

How Variation occurs in Offspring?

There are two types of variation in reproduction which are mentioned below:

Variation in Asexual Reproduction

In this type of reproduction only a single parent is involved in the reproduction. In asexual reproduction there is not much variation seen in these kind of offspring therefore only little changes are been seen. Due to the inaccurate happening during DNA copying mechanism only little variation happens in these type of reproduction. For example: Little changes are seen in fruits and vegetables due to single parent involvement.

Variation in Sexual Reproduction

In this type of reproduction two parents are involved due to fusion of gametes from the two different individuals. When there are two different individual then their genes mixed and then it causes maximum number of variations in their offspring. These offspring looks different from the parents. Further this variation is transferred from generation to generation which maintains the genetic continuity. For example: The offspring of Human being shows accumulation of variation.

Importance of Variation

Some of the important variation are being mentioned below:

• Due to the variation in an individual variation occurs.
• With the help of variation we are able to differentiate whether the offspring of a parent is produced by sexual or asexual reproduction.
• With the help of variation it is also easy to adapt any condition like climatic condition or change in temperature.
• From one generation to other generation variation always leads to good and healthy gene.

Need of Variation

Some of the needs are mentioned that why organisms need variation-

• It helps other organisms or generation to adapt the physical conditions.
• With the help of variation organisms give rise physically different organisms from the parent.
• It also lays a foundation among organisms and can makes up the raw materials for the evolution purpose.

Long-term consequences

In accumulation of variation evolution in organisms is the main consequences for long term in which the organism body structure and functions are varying from each other. This results in the formation of two different types of organisms are being produced from the same family. Accumulation of variation further result in the formation of new species which can adapt to the changes more effectively than the existing ones.

FAQs on Accumulation of Variation During Reproduction

1. What do you mean by Heredity?

Heredity is defined as the transfer of genetic heritage which is passed down from the biological parents to the offspring’s by the process of fertilization. Example – Two blue eyed parents give birth to blue eyed child.

2. Discuss Accumulation of Variation during Reproduction?

The process by which the genetic variation is increased in population through overtime is known as accumulation of variation. Asexual reproduction consists of less variation whereas in sexual reproduction lot of variation in physical characteristics are shown.

3. What is the Importance of Variation during Reproduction?

The main importance of variation is it the help to differentiate whether the offspring of a parent is produced by sexual reproduction or asexual reproduction.

4. Write an example how Variation leads to the formation of New Species?

Broccoli is a man made vegetable and also it is the best example of hybrid species which result of hybrid between Cabbage and Cauliflower.

5. In a species all the Variations does not have equal chances of Survival. Discuss

It depends on the nature of variations as different types of organisms have different kinds of benefits and disbenefits. Therefore the organisms which can adapt the environment will survive and rest will die. This is the reason that all variation does not have equal chances of survival.

6. What are the Two Modes of Variation in Reproduction?

The two mode of reproduction in variation are:

• Variation in asexual reproduction.
• Variation in sexual reproduction.