1. Punnett Squares

2.  __________ allele: always shows up when the allele is present, represented by a capital letter (R)  __________ allele: is hidden when the dominant allele is present, represented by a lowercase letter (r) Dominant Recessive

3.  ___________: an organism’s physical appearance (round/wrinkled seeds)  __________: an organism’s genetic makeup (RR, Rr, or rr) Phenotype Genotype

4.  _____________: a genotype with 2 of the same alleles (RR or rr)  ______________: a genotype with 2 different alleles (Rr) Homozygous Heterozygous

5.  A chart that shows all the possible allele combinations (genotypes) the offspring of two parents can have.

6. 1. Draw a box and divide it into 4 squares.

7. 2. Write the male parent’s alleles along the top of the square and the female parent’s alleles along the left side. Example: Father-Rr Mother-Rr R=round seeds r=wrinkled seeds

8. 3. Copy the female parent’s alleles into the boxes to their right. Example: Father-Rr Mother-Rr

9. 4. Copy the male parent’s alleles into the boxes beneath them. Example: Father-Rr Mother-Rr

10. 5. The completed Punnett square shows all the possible genotypes of the offspring. Example: Father-Rr Mother-Rr

11. A Punnett square can be used to calculate the probability that a certain combination of alleles will result.  Probability offspring will be RR: ___out of ___ or ____% 14 25

12. A Punnett square can be used to calculate the probability that a certain combination of alleles will result.  Probability offspring will be Rr: ___out of ___ or ____% 24 50

13. A Punnett square can be used to calculate the probability that a certain combination of alleles will result.  Probability offspring will be rr: ___out of ___ or ____% 1 4 25

14. You can also calculate the probability of the phenotypes. R=round seeds r=wrinkled seeds  RR and Rr produce _______ seeds: : ___out of ___ or ____% round 3 4 75

15. You can also calculate the probability of the phenotypes. R=round seeds r=wrinkled seeds  rr produces _________ seeds: : ___out of ___ or ____% wrinkled1 4 25

16. Fur color of mice: Dominant allele: Recessive allele: F (black fur) f (white fur)

17. 1.Purebred black mouse (FF) x purebred white mouse (ff) Probability of: FF: ___ out of 4 or ___% Ff: ___ out of 4 or ___% ff: ___ out of 4 or ___% Probability of: Black mouse: ___ out of 4 or ___% White mouse: ___ out of 4 or ___%

18. 1.Purebred black mouse (FF) x purebred white mouse (ff) FfFfFfFf FfFfFfFf F F f Probability of: FF: ___ out of 4 or ___% Ff: ___ out of 4 or ___% ff: ___ out of 4 or ___% Probability of: Black mouse: ___ out of 4 or ___% White mouse: ___ out of 4 or ___% 0 0 00 4 100 (FF, Ff) 4 100 00 (ff)

19. 2.White mouse (ff) x white mouse (ff) Probability of: FF: ___ out of 4 or ___% Ff: ___ out of 4 or ___% ff: ___ out of 4 or ___% Probability of: Black mouse: ___ out of 4 or ___% White mouse: ___ out of 4 or ___%

20. 2.White mouse (ff) x white mouse (ff) ffff f f f Probability of: FF: ___ out of 4 or ___% Ff: ___ out of 4 or ___% ff: ___ out of 4 or ___% Probability of: Black mouse: ___ out of 4 or ___% White mouse: ___ out of 4 or ___% 0 0 100 4 0 0 (FF, Ff) 0 0 100 4 (ff)

21. 3.White mouse (ff) x heterozygous mouse (Ff) Probability of: FF: ___ out of 4 or ___% Ff: ___ out of 4 or ___% ff: ___ out of 4 or ___% Probability of: Black mouse: ___ out of 4 or ___% White mouse: ___ out of 4 or ___%

22. 3.White mouse (ff) x heterozygous mouse (Ff) FfFfFfFfff f f F f Probability of: FF: ___ out of 4 or ___% Ff: ___ out of 4 or ___% ff: ___ out of 4 or ___% Probability of: Black mouse: ___ out of 4 or ___% White mouse: ___ out of 4 or ___% 0 0 50 2 2 (FF, Ff) 2 50 2 (ff)