Explain the mechanism of hereditary changes. - Science and Technology 2

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Short Note

Explain the mechanism of hereditary changes.

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Solution 1

Hereditary changes can occur due to the following changes:

  1. Natural Selection- One allele is fixed for the population as it provides a survival advantage.
  2. Genetic Drift- Sudden change in a small population due to which genetic variability is reduced.
  3. Mutations- Sudden and inheritable changes in the genetic material that gives rise to a new allele.
  4. Recombination- When the crossing over occurs during meiosis, the sequence of alleles changes on the chromosomes.

Solution 2

The mechanism of hereditary changes is as follows:

  1. Diversity or hereditary changes occur due to genetic variation.
  2. In sexually reproducing organisms, a fusion of gametes from male and female parents occurs, the offspring always has recombined genes of both the parents. These offsprings thus show some characters of either of the parents.
  3. Also, sometimes sudden changes known as mutations occur in the genes.  A change in the position of even a single nucleotide can cause either a minor effect or a considerable alteration in the characters of an individual.
  4. If these changes (mutation) occur in the DNA of germline cells then, these changes would be inherited to the next generation.
Concept: Heredity
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Chapter 1: Heredity and Evolution - Answer the following questions

APPEARS IN

SCERT Maharashtra Question Bank 10th Standard SSC Science and Technology 2 Maharashtra State Board
Chapter 1 Heredity and Evolution
Answer the following questions | Q 1.2
Balbharati Science and Technology Part 2 10th Standard SSC Maharashtra State Board
Chapter 1 Heredity and Evolution
Exercises | Q 5.2 | Page 11

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