Which one of the following best describe the product of a gene?

Which one of the following is not one of the major mechanism by which the environment may influence the expression of a gene?

Match the allele combination with the correct term used to describe that genotype combination.

X inactivation can cause mosaicism in mammalian females.  In mosaicism, the phenotype associated with a particular X-linked gene differs in various parts of the body.  A good example is the tortoiseshell cat, which expresses orange fur in some parts of her body and black fur in other parts of her body.  Which one of the following best describe the genotype associated with a mosaicism phenotype?

Blah   Blah

Which one of the following best describes the relationship between allele dominance and frequency of the allele in the population?

Coat color in the calico cat is one of the classic examples of X-inactivation.  Examine the illustration of the tortoiseshell cat below and answer the associated questions.        a.  Which X-linked allele is inactive in the orange patches of the calico cat?      b.  Which X-linked allele is inactive in the white areas of the calico cat?      c.  Is this cat most likely a female or a male?  How do you know?

Three children have the following blood types: Type A, Type A, and Type O.  Which one of the following could not be the blood types of the parents?

You suspect that a particular phenotype is the result of several genes being expressed together (polygenic inheritance).  You decide to document the occurrence of the phenotype in a population, so you sample about 1,000 people.  Which of the following characteristics are you likely to document if the phenotype actually is polygenic?  Select all correct choices.

Which one of the following correctly describes the activity of the Xist gene responsible for X-inactivation?