PRACTICE PUNNETTS TEST REVIEW

PRACTICE PUNNETTS TEST REVIEW
On a separate sheet of paper (or in your notebook) draw a punnett square for each cross.
Write the genotypic ratio and the phenotypic ratio for each cross.
Monohybrid Cross
1. In English bull pigs the allele for a black coat color (B) is dominant over the allele for a brown
coat color (b). Cross a brown bull pig is crossed with a heterozygous black bull pig. Show your
work!
Incomplete Dominance
2. A red rose (RR) is crossed with a white (WW) rose results in ALL pink roses (RW), which
indicate incomplete dominance. What would be the result of a cross between a pink and a red
rose? Show your work!
Co Dominance
3. A Blue Fire Beetle is crossed with a Red Fire Beetle resulting in ALL offspring that are red and
blue spotted (or patchwork), which indicate Co dominance. What would be the result of a
cross between a Spotted beetle and a Red Beetle? Show your work!
Sex-Linked Trait
4. Colorblindness is a recessive, X-linked trait. In marriages between a man who can see color
(XCY), and a woman who is a carrier (XCXc) what percentage of their children can be expected
to be daughters who are carriers? What percentage of their children are boys that can see
color.
5. If several bean plants with the genotype TtYy are crossed with pea plants with the genotype
TTyy, what percentage of the offspring will be expected to have the TTyy allele combination?
(Make a separate Punnett square for each trait).
Blood Types
Is it possible for an AB father and O mother to have an AB son. Use a Punnett square to prove
or disprove.
Parents
#1
Parents
#2
Parents
#3
IA i and IB i IA i and ii IA IB and ii
Baby Baby Baby
#1
#2
#3
IBi ii
IA IB
PRACTICE PUNNETTS TEST REVIEW
On a separate sheet of paper (or in your notebook) draw a punnett square for each cross.
Write the genotypic ratio and the phenotypic ratio for each cross.
Monohybrid Cross
1. In English bull pigs the allele for a black coat color (B) is dominant over the allele for a brown
coat color (b). Cross a brown bull pig is crossed with a heterozygous black bull pig. Show your
work!
Incomplete Dominance
2. A red rose (RR) is crossed with a white (WW) rose results in ALL pink roses (RW), which
indicate incomplete dominance. What would be the result of a cross between a pink and a red
rose? Show your work!
Co Dominance
3. A Blue Fire Beetle is crossed with a Red Fire Beetle resulting in ALL offspring that are red and
blue spotted (or patchwork), which indicate Co dominance. What would be the result of a
cross between a Spotted beetle and a Red Beetle? Show your work!
Sex-Linked Trait
4. Colorblindness is a recessive, X-linked trait. In marriages between a man who can see color
(XCY), and a woman who is a carrier (XCXc) what percentage of their children can be expected
to be daughters who are carriers? What percentage of their children are boys that can see
color.
5. If several bean plants with the genotype TtYy are crossed with pea plants with the genotype
TTyy, what percentage of the offspring will be expected to have the TTyy allele combination?
(Make a separate Punnett square for each trait).
Blood Types
Is it possible for an AB father and O mother to have an AB son. Use a Punnett square to prove
or disprove.
Parents
#1
Parents
#2
Parents
#3
IA i and IB i IA i and ii IA IB and ii
Baby Baby Baby
#1
#2
#3
IBi ii
IA IB