In the AB blood group the two genes are

Options

A. codominant
B. corecessive
C. incompletely dominant
D. dominant-recessive

Answer

**Step-by-Step Solution:**

1. **Understanding Blood Groups**: Blood groups are determined by specific alleles. The ABO blood group system consists of three alleles: A, B, and O.

2. **Identifying Alleles in AB Blood Group**: In individuals with AB blood group, the alleles present are A and B.

3. **Dominance of Alleles**: Both A and B alleles are dominant. This means that when both are present, they will both be expressed in the phenotype.

4. **Co-dominance Concept**: Since both A and B alleles are expressed simultaneously in the AB blood group, they are referred to as co-dominant alleles. This is different from simple dominance where one allele masks the effect of another.

5. **Recessive Allele**: The third allele, O, is recessive. This means that it does not express itself in the presence of either A or B alleles.

6. **Conclusion**: Therefore, in the AB blood group, the two genes (alleles) are A and B, which are co-dominant.

**Final Answer**: The two genes in the AB blood group are A and B, which are co-dominant.

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