All questions please All questions please 78 In dogs, black coat color is domina
ID: 197569 • Letter: A
Question
All questions please
All questions please 78 In dogs, black coat color is dominant over chocolate (brown) coat color, and short hair is dominant over long hair. Two dihybrid dogs (heterozygous for both traits) are crossed. Work out the Punnett square for this cross and answer the following questions: 4. What are the phenotypes of the parents? 5. What are the genotypes of the parents? 6. What percentage of the puppies will be black and short haired? 7. What percentage of the puppies will be chocolate and short haired? 8. What percentage of the puppies will be black and long haired? 9. What percentage of the puppies will be chocolate and long haired?
Explanation / Answer
Lets assume black colour =B, chocolate colour is b and B is dominating over b.
short hair = A, long hair=a, where A is dominates a
AaBb X AaBb
AB
Ab
aB
ab
AB
AABB
Black, short
AABb
Black,short
AaBB
Black, short
AaBb
Black, short
Ab
AABb
Black, short
AAbb
Black, long
AaBb
Blackk, short
Aabb
Black, long
aB
AaBB
Black, short
AaBb
Black,short
aaBB
chocolate,short
aaBb
chocolate, short
ab
AaBb
Black, short
Aabb
Black, long
aaBb
chocolate, short
aabb
chocolate, long
Black short , black long, chocolate short, chocolate long
9:3:3:1
4. phenotypes of parent: black, short
5.genotype of parent: AaBb
6. the percentage of puppy with black and short hair =9/16 X 100=56.25 or 56
7.the percentage of puppy with chocolate and short hair = 3/16 X 100=18.75 or 19
8.the percentage of puppy with black and long hair =3/16 X 100=18.75 or 19
9. the percentage of puppy with chocolate and long hair =1/16 X 100=6.25 or 6
AB
Ab
aB
ab
AB
AABB
Black, short
AABb
Black,short
AaBB
Black, short
AaBb
Black, short
Ab
AABb
Black, short
AAbb
Black, long
AaBb
Blackk, short
Aabb
Black, long
aB
AaBB
Black, short
AaBb
Black,short
aaBB
chocolate,short
aaBb
chocolate, short
ab
AaBb
Black, short
Aabb
Black, long
aaBb
chocolate, short
aabb
chocolate, long