When Gregor Mendel was developing his ideas of inheritance of characteristics, molecular genetics was not yet discovered. Explain in your own terms, why his two most important ant laws have stood the test of time. What assumptions about them were correct? Describe a scenario in which patterns of inheritance did NOT adhere to Mendelian genetics. When Gregor Mendel was developing his ideas of inheritance of characteristics, molecular genetics was not yet discovered. Explain in your own terms, why his two most important ant laws have stood the test of time. What assumptions about them were correct? Describe a scenario in which patterns of inheritance did NOT adhere to Mendelian genetics. Solution At the time of Gregor Mendel, the molecular genetics was not yet discovered but he was a statistician by training and fortunately started his study on pea plant growing in his church lawn. By careful observation and applying statistical inference, he came up with his two laws i.e. law of segregation and law of independent assortment. Law of segregation states that the factors do not mix with each other but maintain their identity and segregates (separate from each other) at the time of meiosis when gametes form (Meiosis was not discovered at that time but people knew about gametes). The other law was law of independent assortment which stated that the factors responsible for different traits assort independent of each other into gametes giving rise to all types of genotypes in F2 generation. His careful observation and mathematical background enabled him to make robust inferences which stood the test of time. The assumptions that were correct were that every factor has two alternative forms. These forms do not mix with each other and segregate in each generation when gametes are formed. There was another law that is law of dominance which states that one form of the factor is dominant over the other due to which the effect of latter is suppressed. But because only 2 laws were asked so we will put the best laws. A scenario in which pattern of inheritence did not adhere to Mendelian genetics is linkage. As many genes are present on same chromosomes, they can not assort independent of each other resulting in linkage. The amount of recombination will depend upon the distance between two genes but in general, these genes are not assorting independently..