Question

If a particular gene is located on the Z chromosome of this lizard species, describe why a lizard with a ZW genotype has a greater probability of expressing the recessive phenotype for the trait than a lizard with the ZZ genotype does.

Answer 1

Answer:

The ZW is the sex-determination system for offsprings for some organisms such as birds, some reptiles etc.

According to this system, the females have the sex chromosomes Z and W. Males have the sex chromosome ZZ.

Females have a greater chance for expressing a recessive phenotype because they will need only one recessive allele on their Z chromosomes to express the recessive phenotype. On the contrary, males will have a lesser chance because in order to show the recessive phenotype they would require both the alleles on the Z chromosomes to be recessive.