Variation: Meaning of Variation and Examples of Genetic Variation

Doorsteptutor material for IAS is prepared by world's top subject experts: Get detailed illustrated notes covering entire syllabus: point-by-point for high retention.

Download PDF of This Page (Size: 260K)

Meaning of Variation

  • It can be defined as any difference between the cells, individual organisms, or groups of organisms of any species.

  • This difference is being caused either by genetic differences (genotypic variation) or by the effect of environmental factors on the expression of the genetic potentials (phenotypic variation).

  • They can be further classified as continuous or quantitative.

    • Smoothly grading between two extremes.

    • With many individuals at the center.

    • Variation of height among human population.

  • Discontinuous or qualitative.

    • Well-defined classes.

    • Variation of blood groups in humans.

  • These variations may be shown in.

    • Mode of reproduction

    • Physical appearance

    • Metabolism

    • Fertility

    • Learning and mental ability

    • Another obvious or measurable characters

Examples of Genetic Variation

  • Eye colour

  • Blood type

  • Camouflage in animals

  • Leaf modification in plants

Polymorphic Variation

  • The separation of higher organisms into males and females.

  • An occurrence of several forms of a butterfly of the same species.

  • Each of the species is colored to blend with a different vegetation.

Importance of Variation

  • It allows some individuals within a population to adapt to the changing environment.

  • More phenotypic variation is enabled by a more genetic variation within a population.

  • It plays an important role in survival of different species.

  • They enable human beings to improve the races of important plants and animals.

  • It further provides variation amongst individuals for natural selection to act upon.

Sources of Variation

Mutation

It creates new variation by changing parts of the genetic code.

Gene Shuffling (Recombination)

  • It creates new variation by the reshuffling of genes during sexual reproduction.

  • Chromosome segregation

  • Crossing-over

DNA Shuffling

DNA Shuffling

Loading Image

Three Sources of Variation

Mutation Recombination Immigration of genes

Three Sources of Variation

Loading Image

Quality Variation

The law of variation defines the difference between an ideal and an actual situation.

Variation or variability:

  • A change in data

  • Expected outcomes

  • Slight changes in production quality

FAQs

Q 1. What are the examples of variations?

Answer:

Examples of variations are eye color, blood type, camouflage in animals, and leaf modification in plants.

Q 2. What is the importance of Variation?

Answer:

Following are the importance of Variation:

i) It allows some individuals within a population to adapt to the changing environment.

ii) More phenotypic variation is enabled by a more genetic variation within a population.

iii) It plays an important role in survival of different species.

iv) They enable human beings to improve the races of important plants and animals.

v) It further provides variation amongst individuals for natural selection to act upon.

Q 3. What is quality variation?

Answer:

  • The law of variation defines the difference between an ideal and an actual situation.

  • Variation or variability:

    • A change in data

    • Expected outcomes

    • Slight changes in production quality

Q 4. Define Gene Shuffling.

Answer:

  • Gene Shuffling creates new variation by the reshuffling of genes during sexual reproduction.

  • Chromosome segregation

  • Crossing-over