# Inheritance

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#1
I'm stuck at these three question.
#1 In humans, the allele for red hair, b, is recessive to the allele for brown hair, B. A man and his wife both have brown hair. They have five children, three of whom have red hair, while two have brown hair. Explain how this may happen, using a genetic diagram to explain your answer.
#2 In Dalmatian dogs, the allele for black spots is dominant to the allele for liver spots. If a breeder has a black-spotted dog, how can he or she find out whether it is homozygous or heterozygous for this characteristic? Use genetic diagrams to explain your answer.
#3 A man of blood type A married a woman of blood type B. They had three children, of blood types O, B and AB, respectively. What are the genotypes of the parents and children? Use genetic diagrams to explain your answer.
I would appreciate if someone could help me!
Thank you!!!
Last edited by Kittykatbot; 3 months ago
0
3 months ago
#2
#1Do a punnett square with both of them being heterozygous, Bb and Bb and show they have a possibility for red-haired children (should be 3:1 brown:red)
#2Breed it with a Liver spotted dog and if there are any dogs with liver spots produced then it is heterozygous, if none are produced it's homozygous. Again draw a punnet square with one of them being a cross between a DD and a dd and one with a Dd and a dd.
#3 AO, BO and then the children are OO, BO and AB as the parents being AO and BO means they could have children with the blood group AO, AB or BO but if either of them where homozygous so AA or BB then it would only be AO and AB or BO and AB.
0
#3
(Original post by kubes_04)
#1Do a punnett square with both of them being heterozygous, Bb and Bb and show they have a possibility for red-haired children (should be 3:1 brown:red)
#2Breed it with a Liver spotted dog and if there are any dogs with liver spots produced then it is heterozygous, if none are produced it's homozygous. Again draw a punnet square with one of them being a cross between a DD and a dd and one with a Dd and a dd.
#3 AO, BO and then the children are OO, BO and AB as the parents being AO and BO means they could have children with the blood group AO, AB or BO but if either of them where homozygous so AA or BB then it would only be AO and AB or BO and AB.
Okay. Thank you so much! :-)
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