Final answer:
The Lyon hypothesis explains dosage compensation in females by the inactivation of one X chromosome, which is important for maintaining gene expression balance between males and females.
Step-by-step explanation:
The Lyon hypothesis is associated with dosage compensation in females. This hypothesis, proposed by geneticist Mary Lyon, states that one of the two X chromosomes in females is randomly inactivated during embryonic development, resulting in a Barr body. This process ensures that females, like males, have only one functional X chromosome in each cell, providing a mechanism for dosage compensation for genes on the X chromosome.
In response to the review questions, X-linked recessive traits are observed more frequently in males than females because males have only one X chromosome and therefore need only one copy of the recessive allele for the trait to be expressed. The recombination frequency that corresponds to perfect linkage is 0 and violates the law of independent assortment. The recombination frequency that indicates independent assortment is 50% or 0.5, as this reflects a lack of linkage between genes. Genetic recombination occurs through the process of crossing over.