And nowadays we know that these two hereditary factors are simply the genes found on homologous chromosomes and we'll see exactly what that means in just a moment. So basically he argued that because this tall f one generation offspring contains that short trade but the short trade is not being expressed. That means the tall trade is actually dominant over that short trade which is said to be recessive. So to see what we mean, let's take a look at the following diagram. So this is the tall true breeding plant. And what that means is it contains two genes that are both essentially tall.