In this article we will discuss about the chromosomal theory of inheritance. The chromosomes as well as genes occur in pairs. The two alleles of a gene pair are located on homologous sites on homologous chromosomes. According to this theory: (i) All hereditary characters are carried with sperms and egg cells as they provide bridge from one generation to the [...]
In this article we will discuss about the linkage and recombination of genes. Morgan and his group observed in Drosophila that when the two genes in a dihybrid cross were situated on the same chromosome, the proportion of parental gene combinations were much higher than the non-parental type or new combinations (also called recombination) of genes. They also found that [...]
The following points highlight the seven main exceptions to the principle of dominance and paired factors. The exceptions are: 1. Incomplete Dominance 2. Co-Dominance 3. Multiple Alleles 4. Test Cross 5. Pleiotropy 6. Polygenic Inheritance 7. Complementary Genes. Exception # 1. Incomplete Dominance: It is a phenomenon in which phenotype of the F1 hybrid offspring does not resemble any of [...]