Mutt Mixer Modeling

Using dogs and alleles based on Mutt Mixer, students model how an individual makes reproductive cells with different combinations of alleles and how reproductive cells join to make varied offspring.

1. Distribute materials. Each student or pair will need 2 parent dog cards, an Instructions page, a Student Sheet, and a Gametes page.
   • Note: Parent dog cards should be printed in color. These and the instructions pages can be re-used.
2. Set a method for randomly assigning alleles to eggs and sperm (flip a coin, roll a die). Students should repeat the randomization process for each gamete.
3. Students will need some information about the traits from Mutt Mixer to complete the table on the Student Sheet. They can use the Edit feature in Mutt Mixer to input their pup’s allele combinations for one of the dog parents. Alternatively, you could give them the information they need from the Mutt Mixer Trait Quick Reference pdf.

Optional: Students can make a visual representation of their pup by taking a screen shot from Mutt Mixer or drawing their pup.

This activity is meant to unpack the idea of random assortment (of parental alleles into gametes) that happens behind the scenes in Mutt Mixer. Try to keep the discussion focused there, as a source of variation in the dog offspring.

• During sexual reproduction, allele shuffling generates offspring with nearly endless trait variations.
• Offspring that arise from sexual reproduction have genetic information from two parents; half of the offspring's genetic information comes from each parent.
• Individuals with two parents have two copies of every gene; the copies may be the same or different.
• Gene versions (alleles) are randomly shuffled with each reproductive event, with offspring inheriting one of each parents' two alleles.

Copies
Optional: Blank paper, colored pencils or crayons for drawing dog offspring, student devices

Mutt Mixer Modeling (pdf)
Mutt Mixer
Mutt Mixer Quick Reference (pdf)

How does the distribution of alleles into reproductive cells lead to genetic variation in offspring?

How does the joining of random reproductive cells lead to genetic variation in offspring?