Biology XII: 5 Prin of Inher & Vari(5 Chromosomal Theory of Inherit

Chromosomal Theory of Inheritance Rediscovery of Mendel’s Work Mendel’s work remained unrecognised for several years because of the following reasons. Lack of communication and publicity His concept of factors (genes) as discrete units that did not blend with each other was not accepted in the light of variations occurring continuously in nature. Mendel’s approach to explain biological phenomenon with the help of mathematics was also not accepted. In 1990, three scientists Hugo deVries, Correns and Von Tschermak independently rediscovered Mendel’s work. Chromosomal Theory of Inheritance By 1900, due to the advancement in microscopy, chromosomes were also discovered. Sutton and Bovery discovered that the behaviour of chromosomes was parallel to the behaviour of genes. Chromosomes and genes both occur in pairs—two alleles of a gene pair are located on homologous sites of homologous chromosomes. Sutton and Bovery further proposed that it is the pairing and separation of a pair of chromosomes that ultimately leads to segregation of the pair of factors they carry. Union of knowledge of chromosomal segregation with Mendelian principles constitutes chromosomal theory of inheritance.