Mendel's Laws, excerpt 2 MIT 7.01SC Fundamentals of Biology
PROFESSOR: Mendel's second law-- this thing over here about a three to one ratio about a single trait being controlled by a pair of alleles, and those alleles being distributed independently of each other to the offspring, the stuff you always learned about Mendel-- that's often referred to as Mendel's first law. Mendel, by the way, didn't call it Mendel's first law. It's considered-- you don't write that in your own papers or something like that, right? So Mendel did actually observed some other things beyond this independent segregation of the alleles for a single trait. Mendel began to cross his peas together and try to make combinations. He had rounds and wrinkles. He had greens and yellows, talls and shorts. He started making combinations. How about a plant that was wrinkled and yellow? Green was the normal color. Round was the normal shape. But he had yellows. He had wrinkleds. How about making a combination? So he begin to make plants th...