lethal genes do not necessarily have to be recessive. Some genes produce a dominant phenotypic effect in heterozygotes but are llethal in the homozygous dominant condition. For example, the gene for creeper in chickens is dominant, producing fully viable, but abnormal, heteerozygotes, which have shortened, crooked legs. In the homozygous condition, the creeper gene results in the death of the embryo on about the forth day of incubation. A gene such as CREEPER is an incompletely dominant lethal gene.
In a cross between two creepers, three-quarters of the eggs hatched. What fraction of the chicks should be creepers? What fraction should be normal? What phenotypic ratio would you expect from a cross between a creeper and a normal chicken?
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10 pts b.a.! mendelian genetics help plz!?
This is a confusing one. The cross between the normal chicken and the creeper if the normal chicken is homozygous for normal and dominant traits, and the creeper is heterozygous the offspring ratio of normal to creepers if four offspring were created is: 1:1 or 50%
Ihope this makes sense and helps.
Reply:i really wish i could answer your question but i can't i am gonna study genetics next semester i am studying chemistry right now so soory i can't help!
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