Answer to Question #190899 in Genetics for Muhammed islam

Question

How is the behaviour of chromosomes during cell division leading to variation? 

Answer 1

During meiosis, homologous chromosomes (1 from each parent) pair along their lengths. The chromosomes cross over at points called chiasma. At each chiasma, the chromosomes break and rejoin, trading some of their genes. This recombination results in genetic variation.