Blood flow is influenced by stenosis and magnetic field. Stenosis obstructs the blood motion and changes the blood velocity and pressure and that can be maintained by the application of magnetic effect. It is also considered that natural blood flow is laminar though blood's Reynolds number is very high. Mendel's mathematical explanation on gene is extended, which can analyse the dissimilarities amongst the hybrids. A creature of a species may have two or more distinction in a trait e.g. a flower's petal may carry more than two colours and that can be analysed mathematically. There is a genealogical percentage to exhibit each distinct characteristic of a trait. The cause of the loss of a particular species of living organism can be discussed.