Answer:
C) B positive is the right answer
Explanation:
Codominance
ABO blood group is an example of co dominance. According to this
Two alleles are both dominant, So A and B are both co dominant, they will express and I allele which will be recessive.
Type A-------------- AA or Ai
Type B---------------BB or Bi
Type AB------------- AB
Type O--------------- ii
Rh antigen is dominant to Rh- (for positive and negative due to presence of Rh antigen
So for Rh+ = RR (homozygous dominant) and Rr (heterozygous dominant)
Rh-= rr (homozygous recessive)
Given conditions in the questions
Given type Alleles for type Allele for Rh antigen
Type A Woman A+ Ai Rr
Daughter Type O+ ii R?
Son type B- Bi rr
Father type Bi Rr or rr
• As mother is A positive, so definitely the son got his B allele from the father, so father should have allele.
• So as the daughter is ii, so it means the daughter is getting one i allele from mother and other i allele came from the father
• As the son have B allele which comes from father, so what is son getting from mother? Definitely he is getting i allele from mother because that the only way mother can donate to the son and not change his blood type.
• No we know that the son is rr for Rh antigen, which means that he is getting one r from mother because she must have a little r to donate to her son and one r from father
The father is either type B Positive BiRr or type B Negative Birr, but we have no other answer than type B positive in the multiple option. This is the possibility
