Linkage or crossing-over of genes are alternatives of each other. Justify with the help of an example.

Solution

Linkage is the tendency for two or more non-allelic genes to be inherited together, because they are located more or less closely on the same chromosome.
Crossing over is the process by which two homologous chromosomes pair up and exchange sections of the coiled DNA.
If linkage is high the crossing over will be low.
If linkage is less the crossing over will be more.

In Drosophila a yellow bodied white eyed female was crossed with brown bodied red eyed male, F1 progeny produced and intercrossed the F2 phenotypic ratio of Drosophila deviated significantly from Mendel’s 9:3:3:1, the genes for eye colour & body colour are closely located on the ‘X’ chromosome showing high linkage & therefore inherited together, recombinants were formed due to crossing over but at low percentage.

Some More Questions From Principles of Inheritance and Variation Chapter

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Principles Of Inheritance And Variation

Linkage or crossing-over of genes are alternatives of each other. Justify with the help of an example.

Some More Questions From Principles of Inheritance and Variation Chapter

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What is name of a cross in which a dominant individual is crossed with a recessive parent?

Distinguish between homogametic and heterogametic organisms.

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