18. What are all the possible gamete combination if a parent is homozygous dominant for one trait and heterozygous for the other trait (AABb only)? (Select all that apply) bb ab Aa BB aa Ab AB c aB

## Step 1<br />The problem involves understanding the principles of genetics, specifically the concept of gamete formation. A parent with the genotype AABb is homozygous dominant for one trait (AA) and heterozygous for the other trait (Bb). <br /><br />## Step 2<br />During gamete formation, each gamete will receive one allele from each gene. This is due to the law of segregation, which states that allele pairs separate independently in the formation of gametes.<br /><br />## Step 3<br />The possible combinations of alleles that a gamete can receive are: AB, Ab, aB, and ab. These combinations are formed by taking one allele from each gene.<br /><br />## Step 4<br />The options bb, Aa, BB, aa, and c are not possible gamete combinations for this parent. This is because the parent is homozygous dominant for one trait (AA) and heterozygous for the other trait (Bb). Therefore, the gametes cannot have the bb, Aa, BB, aa, or c combinations.