can anyone explain fig 5.9 in ncert text page 82 and fig 5.11 of page 84....???
Fig. 5.9. Mendel's principle of independent assortment found cytological proof from the fact that members of one pair of homologous chromosome move to the poles independently of the members of another pair. Means chromosome behave as individual units during inheritance. The independent nature of chromosomes can be directly studied under microscope during meiotic cell division. The mendel factors also behave in the same way. In the fig., four different colored chromosomes are shown. In the first case, orange and green are segregating together but in another case orange segregates with red. So, Sutton and Boveri mix these concepts of chromosomal segregation with mendelian principles and give chromosomal theory of inheritance.
Fig. 5.11 Morgan conducted 2 dihybrid crosses. In cross A, gene y and w are crossed and in cross B, there is a cross between gene w and m. Morgan observed that even when genes were grouped on the same chromosomes, few genes were tightly linked (with low rate of recombination) while still others were loosely linked (with high rate of recombination). They observed that white and yellow genes were closely linked with only 1.3% recombination and white and miniature showed 37.2% recombination.