Question

a. for questions 1-9, use the pedigree chart shown below. some of the labels may be used more than once.
use a,b,c, or d for 1-6
______ 1. a male
______ 2. a female
______ 3. a marriage
______ 4. a person who expresses the trait
______ 5. a person who does not express the trait
______ 6. a connection between parents and offspring
______ 7. how many generations are shown on this chart?
assuming the chart above is tracing the dominant trait of \white forelock (f)\ through the family. f is a tuft of white hair on the forehead.
______8. what is the most likely genotype of individual \a\? (ff, ff or ff?)
______9. what is the most likely genotype of individual \c\? (ff, ff or ff?)

Explanation:

Step1: Match symbols to terms

1. Male: Square (C)
2. Female: Circle (A)
3. Marriage: Horizontal line (B)
4. Express trait: Shaded shape (A)
5. No trait: Unshaded shape (C)
6. Parent-offspring link: Vertical line (D)

Step2: Count generations

Top (A,C) = Gen1; Middle row = Gen2; Bottom row = Gen3. Total: 3

Step3: Genotype of A (dominant trait)

A shows the dominant trait. Since her child (unshaded, ff) gets a recessive allele from each parent, A must carry f. Genotype: Ff

Step4: Genotype of C (no trait)

C does not show dominant trait, so has only recessive alleles. Genotype: ff

Answer:

1. C
2. A
3. B
4. A
5. C
6. D
7. 3
8. Ff
9. ff