Practice

Here are a few questions for practice/review.

Match the following F2 phenotypic ratios with the inheritance pattern they are most common in:

1)  1:2:1                          a.  complete dominance
2)  3:1                             b.  dihybrid
3)  9:3:3:1                       c.  incomplete dominance and codominance

4)  What is the type of inheritance in which both alleles are equally expressed?  Give an example discussed in class.
5)  What is the type of inheritance in which two pure-breeding phenotypes produce offspring that have a phenotype that is intermediate between the two parental types?  Give an example discussed in class.
6)  In hamsters, black fur is dominant to brown.  A friend gives you a black hamster.  How could you determine if its genotype is BB or Bb?  (What type of cross would you perform?)
7)  What is the difference between the terms sex-linked gene and linked gene?  (See p. 176 and p. 172.  These terms do not mean the same thing!)  We will begin discussing linked genes tomorrow and calculating recombination frequencies, so I need you to know the difference between these terms.

I will be checking in until around 10:30 if you have questions.  These are good practice, so try them.  If you get stuck, that's okay.  If I can't answer your questions on the blog because you need to see a punnett square or detailed explanation, I will definitely answer them tomorrow.