Practicing these questions and trying to compare and see if Im on the right path

Practicing these questions and trying to compare and see if Im on the right path. thank you.
 

1. Why is dosage compensation necessary?

1. Some forms of human color blindness are inherited as X-linked recessive traits.  Heterozygous females are not color blind, but hemizygous males are.  Sometimes, however, heterozygous females exhibit partial color blindness.
   1. Why would some females who are heterozygotes have partial color blindness?
   2. In very rare cases, some heterozygous females are color blind in one eye but not the other.  How could this happen?

1. What is a reciprocal cross?  What would be the expected outcomes of a gene on an autosome when you cross an organism that is true-breeding wild-type with an organism that is true-breeding recessive?  What would the results be if the gene is maternally inherited?

1. You have a female snail that coils to the right (dextral), but you do not know the genotype.  You know dextral (D) is dominant to sinistral (d).  You have male snails where you know the genotype (you have an assortment of any snails to test with that you wish).  How would you determine the genotype of this female snail?