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If a female has 'A' blood group and her husband has 'O' blood group, then the blood group of their children would possibly be:

Correct answer: B. A and O groups only

  • A. A and B groups only
  • B. A and O groups only
  • C. AB only
  • D. All four groups

Explanation

Option B is correct. The blood group of the children of a woman with type A blood and a man with type O blood can only be type A or type O. The ABO blood group system is determined by the presence of three different alleles of the ABO gene: A, B, and O. The A allele is responsible for the production of the A antigen, the B allele is responsible for the production of the B antigen, and the O allele is responsible for the production of neither antigen.If a woman has type A blood, she must have one A allele and one O allele. If a man has type O blood, he must have two O alleles. The children of this couple will inherit one allele from each parent. There are two possible genotypes for the children: AO and OO. If the children have the AO genotype, they will have type A blood. If the children have the OO genotype, they will have type O blood. It is not possible for the children to have type B blood, because the B allele is not present in either parent.

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About Inheritance

Mendel's laws explain segregation, independent assortment and the prediction of genetic ratios using alleles, genotypes and phenotypes. The chapter also covers linked genes, recombination and crossing over during meiosis, then applies pedigree reasoning to X-linked recessive traits, which show different inheritance patterns in males and females.

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