6. Create a Punnett square to determine the possibility of a couple having a color-blind child if the mother is color blind but the father has normal vision. HINT: Use Xb to indicate an X with the color-blindness trait.
In this case, the mother is color blind which means she carries the color-blindness trait on one of her X chromosomes. The father, on the other hand, has normal vision meaning he carries a normal vision allele on both of his X chromosomes.
To create a Punnett square, let's represent the mother's color-blindness allele as Xb and her normal allele as X. The father's normal vision allele will be represented as X.
Punnett square:
Xb X
------------------
Xb | XbXb XbX
------------------
X | XbX XX
From the Punnett square, we can determine the possibilities:
1. There is a 50% chance of having a color-blind daughter (XbX).
2. There is a 50% chance of having a carrier daughter (XbX).
3. There is a 50% chance of having a normal vision son (XX).
4. There is a 50% chance of having a carrier son (XbX).
Note: Carriers, such as the daughter in this scenario, have one normal allele (X) and one color-blind allele (Xb). They have normal vision but can pass on the color-blindness trait to their children.