Very Short Answer Question. What is crossing over? - Biology

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Short Note

Very Short Answer Question.

What is crossing over?

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Solution

  1. Crossing over is a process that produces new combinations (recombinations) of genes by interchanging and exchanging of corresponding segments between non-sister chromatids of homologous chromosomes.
  2. It occurs during pachytene of prophase I of meiosis.
  3. The mechanism of crossing over consists of four sequential steps such as synapsis, tetrad formation, crossing over, and terminalisation.
  4. The phenomenon of crossing over is universal and it is necessary for the natural selection because it increases the chances of variation.
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Chapter 3: Inheritance and Variation - Exercises [Page 68]

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Balbharati Biology 12th Standard HSC for Maharashtra State Board
Chapter 3 Inheritance and Variation
Exercises | Q 2.4 | Page 68

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