Class 26

   Today in class we were introduced dihybrid crosses and learned different ways to solve dihybrid cross problems. A dihybrid cross involves a study of inheritance patterns for organisms differing in two traits. Mendel invented the dihybrid cross to determine if different traits of pea plants, such as flower color and seed shape, were inherited independently. Our objective is to understand the principles that govern inheritance of different traits in a dihybrid cross that led Mendel to propose that alleles of different genes are assorted independently of one another during the formation of gametes. We did an exercise involving popsicle sticks were we had parents with two different traits and crossed them using steps to make phenotypes and genotype ratios. There are two ways that were shown to solve dihybrid crosses. First we learned Mr. Quicks way of crossing with a punnet square that showed the phenotype and genotypes of the offspring. Then we were shown Mr. Fitz's way that is a bit faster and uses a punnet square for each trait. This Dihybrid cross video helped me understand dihybrid crosses and is similar to Mr Fitz's way of solving the problem. We then took a short quiz and notes on dihybrid crosses.