Ok so imma make this cleaner to make it earlier to understand. :)
H for brown hair
h for red hair
Mother: Hh
(It’s given)
Father: hh
(Saying that it’s isn’t brown; let’s put this instead, we are trying to find the gene for red hair.)
So in the punnet square below, it is shown that there is a 50/50 chance for the offspring to have red hair.
Ration is 1:1.
But there is also another probability for the offspring to be like their mother, have the dominant gene of black hair overruling the recessive gene of red hair.
