Question

incomplete dominance
the philadelphia trout is a species of fish that
exhibits incomplete dominance. there two different
alleles that determine the color of scale on the fish.
c^b produces blue scales while c^y produces yellow
scales. homozygous fish are either blue or yellow.
the heterozygous genotype is a mixture of the two
colors and is green.

1. two green scale fish are crossed

a. what is the probability that they will be blue? ______%
b. what is the probability that they will be yellow? ______%
c. what is the probability that they will be green? ______%

1. a blue and green scaled fish are crossed.

a. what is the probability that they will be blue? ______%
b. what is the probability that they will be yellow? ______%
c. what is the probability that they will be green? ______%

1. two blue scaled fish are crossed.

a. what is the probability that they will be blue? ______%
b. what is the probability that they will be yellow? ______%
c. what is the probability that they will be green? ______%

1. why does incomplete dominance not support the blending hypothesis?

Explanation:

Question 7

Part a

Step1: Determine genotypes of green fish

Green fish are heterozygous, so genotype is \( C^bC^y \) (let \( C^b \) be blue allele, \( C^y \) be yellow allele).

Step2: Set up Punnett square

Cross \( C^bC^y \times C^bC^y \). The Punnett square has four cells: \( C^bC^b \), \( C^bC^y \), \( C^bC^y \), \( C^yC^y \).

Step3: Calculate probability of blue (\( C^bC^b \))

Only 1 out of 4 cells is \( C^bC^b \). Probability is \( \frac{1}{4} = 0.25 \), so 25%.

Step1: Use Punnett square from 7a

Cells are \( C^bC^b \), \( C^bC^y \), \( C^bC^y \), \( C^yC^y \).

Step2: Probability of yellow (\( C^yC^y \))

1 out of 4 cells. \( \frac{1}{4} = 0.25 \), so 25%.

Step1: Use Punnett square from 7a

Cells are \( C^bC^b \), \( C^bC^y \), \( C^bC^y \), \( C^yC^y \).

Step2: Probability of green (\( C^bC^y \))

2 out of 4 cells. \( \frac{2}{4} = 0.5 \), so 50%.

Answer:

25

Part b