Mouse Genetics

http://www.explorescience.com/activities/Activity_page.cfm?ActivityID=39

Read the introduction, then go to Statistics

1. Flip the coin 20 times and use the program to keep track of your flips. How many heads? _____ How many tails? _______

2. What is the probability of getting a head? _______ What is the probability of getting a tail? ____________

3. Was your trial flips statistically accurate? Propose an explanation why you might not get the exact statistical results when you actually flip a coin.

Go to the Second coin flipping activity.

4. Flip the two coins 20 times and keep track of your flips How many times did you flip two heads ________ two tails ________ head and tail _______

5. What is the probability that you will get two head? ________ A head and a tail? ________

6. If two red parents that have both a dominant and recessive allele (Rr) are crossed, what is the probability of having a green offspring? ________

Go to "Simple Mouse House" Play around with breeding different mice, then proceed to the questions.

7. Given two pure black mice, can you produce a white mouse? ______

8. Given a pure black mouse, and a pure white mouse, can you produce a black mouse? _____

9. If you breed two white mice, can you get a black mouse? _______

Go to "Advanced Mouse House"
In this activity, you will need to use the counter feature to keep track of the mice offspring.
First breed a pure white/red eyed mouse with a pure black / black eyed mouse

10. The offspring of this cross is your F1 generation. What color are they? ________

Put two F1 mice in the cage.
Remove the pure parents and place two F1 mice for breeding. Make sure the counter is turned on.
Breed this pair a number of times, until you have 160 total mice.
Use the "clear kids" button to breed them again while keeping track of the numbers.

11. Fill out the data table

	Number of Mice
White fur, black eyes
Black fur, black eyes
White fur, red eyes
Black fur, red eyes

12. Based on this data, is black or white fur dominant? _________ Is black or red eyes dominant? _________

13. Given the following genotypes for the original parental cross: BBEE (black fur, black eyes) and bbee (white fur with white eyes). Show a punnet square for the cross. What is the phenotype and genotype of the offspring (F1 generation)?

14. Show a punnet square for the second cross. BbEe x BbEe. What phenotypes are present and in what proportion.

15. Now, your punnet squares shows 16 possibilities. We did 160 crosses. Calculate the ratios out of 160 instead of 16. Hint, multiply by 10.

16. Compare the expected ratios (from the cross in #13) with the actual phenotypes (your data).

	Expected out of 160	Actual out of 160
White fur, black eyes
Black fur, black eyes
White fur, red eyes
Black fur, red eyes