Punnet Squares

What are they?

The Punnet Square is a diagram to discover all the possible combinations of gene types that can occur in babies that are passed on from the parents.

How the Punnet Square works

First, you place the father's alleles on top of the Punnet Square with a letter above each box. Second, you place the mother's alleles on the left side of the Punnet Square with one letter next to the two left hand side boxes. Then, write a two-letter gene combination from the mother's and father's alleles in each of the squares.

In our example the squares are filled like this:

• Top left square: Bb
• Top right square: bb
• Bottom left square: Bb
• Bottom right square: bb
• Notice how traditionally, the dominant alleles (capital letters) are written first 

You can learn more about Punnet Squares by Clicking Here to do a virtual lab on them.

For more information go to: 

http://anthro.palomar.edu/mendel/mendel_2.htm

http://utahscience.oremjr.alpine.k12.ut.us/sciber00/7th/genetics/sciber/punnett.htm
http://www.bugaco.com/calculators/punnett_square.php#kind=blood
https://www.youtube.com/watch?v=prkHKjfUmMs