Question: how many types of zygotic combinations are possible?
Answer: How many types of zygotic combinations are possible between a cross Aa BB Cc Dd x AA bb Cc DD? The number of possible gamates = 2n, where n is number of heterozygous pairs of genes. When 8 combinations are crossed with 2 combination, the number of zygotic combinations = 8 x 2 = 16.