2. A man with type AB blood is married to a woman also with type AB blood. What proportion of their children will have: Show the cross: A blood? __ B blood? __ Oblood __ AB blood __ A man with type B blood (genotype BB is married to a woman with type O blood. Show the cross: Vhat proportion of their children will have: A blood? __ B blood? __ Oblood __ AB blood __

## Step 1<br />The problem involves understanding the inheritance of blood types in humans. The ABO blood group system is determined by the ABO gene, which has three alleles: \(I^A\), \(I^B\), and \(i\). The \(I^A\) and \(I^B\) alleles are co-dominant, meaning that if both are present, they will both be expressed. The \(i\) allele is recessive and will only be expressed if no \(I^A\) or \(I^B\) alleles are present.<br /><br />## Step 2<br />For the first scenario, both parents have type AB blood. This means they each have one \(I^A\) and one \(I^B\) allele. When they have children, each child will receive one allele from each parent. This can result in four possible combinations: \(I^A I^A\), \(I^A I^B\), \(I^B I^A\), and \(I^B I^B\). These correspond to blood types A, AB, B, and AB respectively. Therefore, the probability of a child having blood type A, B, O, or AB is 1/4, 1/4, 0, and 1/2 respectively.<br /><br />## Step 3<br />For the second scenario, one parent has type B blood (genotype BB) and the other has type O blood (genotype ii). When they have children, each child will receive one allele from each parent. This can result in two possible combinations: \(I^B i\) and \(I^B i\). These correspond to blood types B and O respectively. Therefore, the probability of a child having blood type A, B, O, or AB is 0, 1, 1, and 0 respectively.