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Question
Very Short Answer Question.
What is crossing over?
Solution
- 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.
- It occurs during pachytene of prophase I of meiosis.
- The mechanism of crossing over consists of four sequential steps such as synapsis, tetrad formation, crossing over, and terminalisation.
- 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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