So an uppercase B basically means the individual will not be color blind. And in this particular case, if we suppose, let's suppose that the brown gene shown here is the gene that codes for color blindness. Uppercase B means that's the dominant gene and the individual will not be colorblind. And so because both of these are upper case B's, we have homozygous dominant. Now, likewise, we can also be homozygous recessive. And in this particular case, we have lowercase B, lower case B.