Marbles Is a Manx Cat Whose Tail Is So Short

Multiple Choice

Marbles is a Manx cat whose tail is so short that she appears not to have one.The genotype for short tail in Manx cats is heterozygous (Mm) .Cats that are genotype mm have normal length tails,but cats that are genotype MM die before birth due to highly abnormal brains and spinal cords.Marbles has one copy of a dominant _____ allele.2-14-2013

A) pleiotropic
B) penetrant
C) lethal
D) polymorphic