Dihybrid Crosses Quiz

a. AB
b. Bb
c. aB
d. ab

2. If AaBb is crossed with aabb, what proportion of the offspring would be expected to be aabb?

a. 9/16
b. 1/8
c. 1/4
d. 1/16

3. If the offspring of a cross show a 9/16 to 3/16 to 3/16 to 1/16 ratio (9:3:3:1), the parents of the cross have the genotypes

a. AaBb x AaBb
b. AaBb x aaBB
c. aaBb x aabb
d. aaBb x Aabb

4. Whenever a capital letter is present, a red color is produced. In a cross of AaBb x AaBb, how many red offspring would you expect out of 16?

a. 1
b. 3
c. 9
d. 15

5. Assume that you mated two individuals heterozygous for each of two traits and obtained 80 offspring. How many of them would be expected to look like their parents?

a. 25
b. 45
c. 60
d. 80

6. Genes that assort independently are

a. located on different chromosomes
b. located on the same chromosome
c. alleles of each other
d. dominant

7. If W = purple flower and w = white, and D = tall plants and d = short plants, a wwDd plant would be

a. purple and tall
b. purple and short
c. white and tall
d. white and short

8. If two true-breeding parents are crossed with each other and all the offspring have their mother’s ears and their father’s tail, the parents in the cross would be

a. EETT x eett
b. eeTT x EEtt
c. EeTt x EeTt
d. eeTt x Eett

9. If aaBb is crossed with AAbb, what proportion of the offspring will be AAbb?

a. 0
b. 3/16
c. 9/16
d. 1/4

10. If AaBb is crossed with AaBb, what proportion of the offspring will be dominant for the ‘A/a’ trait and recessive for the ‘B/b’ trait (i.e. A-bb)?

a. 9/16
b. 3/16
c. 1/16
d. 0