Pedigree

Pedigree Activtity..........



Copy this Pedigree on the top half of your paper. Answer questions in complete sentences with no pronouns.

1. (write) Pedigrees can be used to determine a parents genotype.

2. Label the first row in the pedigree “I. Grandparents.” Label the second row “II. Parents.” Label the third row “III. Children.”

3. Label each individual in the pedigree with their phenotype.

4. Does deafness skip a generation or is someone deaf in every generation?

5. What is the genotype of an individual with deafness?

6. What are the two possible genotypes for hearing people in this pedigree?

7. Is any of the Grandparent generation deaf? Is all of the Child generation deaf or not?

8. As evidenced by the answers above, Is the allele for deafness dominant or recessive and how do you know?

9. The three genotypes are homozygous dominant, homozygous recessive, and heterozygous. Write the genotypes of individual numbered 6, 10, and 14 under their circle or square.

10. Look at the offspring on number 6 and 7. The fact that number 7 had deaf offspring means she has a deaf allele. Write the genotype of number 7 under her circle.

11. Children numbered 8, 9, 11, 12, & 13 must get their hearing allele from their mother and their father has only non hearing alleles to provide. Write the genotypes for the rest of the III generation under their circles or squares.

12. Look at the grandparents numbered 1 and 2. Use the fact that they have deaf off­spring to write their genotypes under their circle or Square.

12. Use a Punnett square to figure out the probability of individual number 5 being homozygous dominant verses heterozygous.

13. What are the possible genotypes for the grandparents numbered 3 and 4.

(Alternate Assignment Idea: Have students pick a recessive trait in an organism of their choice. They could make or be given paper doll shapes of this organism. They then could use the above pedigree to modify a paper doll shape to represent each individual in the pedigree. The paper dolls could then be arranged in the shape of the pedigree. The above question would be modified and "fill-in blank" would replace the word "deaf" in each of the above questions. The student would then write the trait they chose in the blanks. The students then would label this paper doll pedigree as indicated and answer the questions.)