Genetics Take-Home Problems

Instructions: Answer the following genetics problems below. SHOW ALL OF YOUR WORK.

1. Red-green color blindness is inherited as a recessive X-linked trait. A man with normal color vision has a child with a woman who is a

carrier for red-green color blindness.

Let XB = Normal vision allele
Let Xb = Red-green color blindness allele

Data Collection/Selection
Using the information above, write the parent genotypes and gametes. Not all blanks may be used.
Parent Genotypes: ______________ x ________________
Parent 1 Gametes: _____ _____
Parent 2 Gametes: _____ _____

Analysis
Organize the data above into a Punnett square and list the F1 genotypes and phenotypes. Be sure to include sex. Not all boxes may be used.
Parent
Gametes
F1 Genotypes: F1 Phenotypes:

Use the information above to answer the following questions.
Conclusion
What fraction of their children will likely be red-green color blind? ____________

Subject Matter
Would the couple be able to father a female child who has red-green colorblindness? Why or why not?

2. A Pea plant that is Homozygous Dominant for purple flower color and Heterozygous for dark green leaves is crossed with another pea

plant that is Heterozygous for both purple flower color and dark green leaves

Let R = Purple flower color and r = white flower color
Let D = Dark Green leaves and d = light green leaves

Data Collection/Selection
Using the information above, write the parent genotypes and gametes. Not all blanks may be used.
Parent Genotypes: ______________ x ________________
Parent 1 Gametes: _____ _____ _____ _____
Parent 2 Gametes: _____ _____ _____ _____

Analysis
Organize the data above into a Punnett square and list the F1 genotypes and phenotypes. Not all boxes may be used.

Parent
Gametes
F1 Genotypes: F1 Phenotypes:

Use the information above to answer the following questions.
Conclusion
What fraction of the offspring will have purple flower color with light green leaves? ____________

Subject Matter
Would the parental plants above be able to produce offspring with white flowers? Why or why not?

WE ACCEPT