Punnett Squares (Remote)

For students who are learning remotely, genetics lessons that involve Punnett squares and probability may be challenging.  In a traditional class, I would give students small whiteboards and we would practice doing crosses together. I could circulate around the room to help students who are struggling, and they could help each other. Plus, for some reason, they love writing on whiteboards!

For remote learning I had to get a little creative with how to walk students through the process of setting up Punnett squares. I had to create something that students could write on that I could also check or monitor from a distance.    Genetics: Focus on Punnett Squares is made with Google Slides and walks students through the steps of setting up Punnett squares and determining phenotypic ratios.  It is designed so that students can type into tables (Punnett Squares) to show the outcome of a cross.   The slides start with simple problems like identifying heterozygous and homozygous, and with squares already set up. Students progress to harder problems where they must determine the genotypes of the parents and set up the squares themselves.

I plan to do this together with my students, requiring them to complete it as we go through the steps.  Then students will work independently on Genetics: Simple Practice Problems which has been modified for remote learning and turn in via Google Classroom. This is a google doc with blanks and tables that students fill in.

Question #4 from Simple Genetics Practice Problems

This year, I don’t think that I will go into much detail about dihybrid crosses except so show one and stress that there will always be a 9:3:3:1 ratio.  The time it takes to set up and complete those large squares and my AP Biology students are taught to use mathematical strategies to solve. I do a practice worksheet for crosses with two traits that I may use with my honors section.

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