Can an A positive father and negative mother produce both children?

Yes, it is possible for an A-positive father and an O-negative mother to have both A-positive and O-positive children. This is due to the way in which blood types are inherited.

A person's blood type is determined by the presence or absence of two antigens, A and B, on the surface of their red blood cells. People with type A blood have only A antigens, those with type B blood have only B antigens, those with type AB blood have both A and B antigens, and those with type O blood have neither A nor B antigens.

The A and B antigens are inherited from our parents, with each parent contributing one allele for each antigen. A person who inherits an A allele from one parent and an O allele from the other will have type A blood, while a person who inherits a B allele from one parent and an O allele from the other will have type B blood. A person who inherits an A allele from one parent and a B allele from the other will have type AB blood, while a person who inherits an O allele from both parents will have type O blood.

In the case of an A-positive father and an O-negative mother, the father can contribute either an A allele or an O allele, while the mother can only contribute an O allele. This means that the possible offspring genotypes are AO (A-positive) and OO (O-positive).