Haploids HB1, HA1, and HA2 could not grow on their own as they could not synthesize their own adenine. This makes sense because they all had an ade mutation that makes them mutant deficient for adenine biosynthesis. Haploid HA0 could grow on its own, meaning that it can synthesize its own adenine. Again, this makes sense because this haploid strain had no mutations in any of its ade genes. The cross between HB1xHA1 did not proliferate. Because the cross contained one MATa and one MATα, sexual reproduction is possible. However, because it did not proliferate, it means that their alleles are not complementary.