I failed to find the options, but I will post the way by which you can construct Punnett squares.
Answer and Explanation:
First, you need to know both parental individuals´ genotypes. From these genotypes, you will get all the possible gametes for each parent, following the principle of simple segregation.
Then, by using a simple square, you will make the crosses. This is:
You will locate all the possible gametes of one parent on the top of the square
You will place all the possible gametes of the other parent on the left edge of the square.
Once you have done that, you will perform the crosses. You will look for the intersection between each parent´s gametes and place all the involved alleles in the intersection-box. These are the possible genotypes, and they will be written within the square.
In the attached files, you will find an example of the cross between two pure-breeding plants.
