The current research article is based on a simple and practical way of employing the computational power of widely available, versatile software MS Excel 2007 to perform interactive computer simulations for undergraduate/graduate students in biology, biochemistry, biophysics, microbiology, medicine in college and university classroom setting. To accomplish this important motive, we developed the necessary computer algorithm, which used a built-in pseudo-random number generating function in MS Excel 2007, to computer model two basic Mendel's Laws of heredity for plant and animal species. We performed more than 18,000 computer simulations to investigate the behavior of dominant and recessive genes to verify two basic Mendel's Laws of heredity. Our simulation work corroborates the experimental observations of Mendel's research on inheritance in "Pisum hybrid species". When we compare our results of simulated data with that of experiments done on "Drosophila melanogaster", fruit fly extensively being used as a model organism to study genetics and development, an exceedingly good agreement between the simulated and the experimental data has been observed for the F2 generation. (Contains 4 tables and 3 figures.)