WAEC Biology 2015 Papers

Concept:Spotted skin is produced by the dominant allele $H$, while black skin is produced by the recessive allele $h$.Explanation:A black panther shows the recessive trait, so its genotype must be $hh$.In the cross, the spotted leopard produces both spotted and black offspring.This is possible only if the spotted leopard carries the recessive allele $h$.Therefore, the spotted leopard must be heterozygous, $Hh$.The black panther must be homozygous recessive, $hh$.The cross $Hh \times hh$ gives $Hh$ spotted and $hh$ black offspring in a $1:1$ ratio.Answer:Spotted Leopard $Hh$ and Black Panther $hh$ (Option D).