Question

A man with blood group A marries a woman with blood group and
their daughter has blood group o. Is this information enough to tell you
which of the traits - blood group A or 0 - is dominant? Why or why not?​

Answer 1

Answer:

The given information is not enough to determine the traits- blood group A or O is dominant.

In ABO blood grouping blood type A is always dominant whereas, the blood type O is always recessive.

Here the father's blood group is A hence, it can either be homozygous (AA) or heterozygous (AO).

The mother's blood group is O and it is only possible if it is heterozygous (OO).

For the daughter to have blood group O the father must be heterozygous (AO) and mother must be (OO).

This is the right answer for your question.