Class Notes (834,149)
Canada (508,378)
Biology (116)
BIOL 2000 (29)

Chapter 6-4.docx

2 Pages
Unlock Document

BIOL 2000
Joseph Rasmussen

Chapter 6-4 Review  1 gene o 3:1 o 1:1 o 1:2:1  2 genes o 3:3:1:1  Aabb x AaBb o 1:1:1:1 o 9:3:3:1 Interfering gene reactions  Understand how the phenotype of a double mutant can be used to infer the relative positions of gene sin a pathway  No gene interaction is indicated in the 9:3:3:1 ratio Analyzing double mutants: variations on the 9:3:3:1 ratio  New phenotype (9:3:3:1) o = Independent gene action (independent pathway)  Getting albino snake (ratio of 1) from orange and black cross (recessive for both means the snake can not make either pigment.  What if we self the Dihybrid resulting from the second cross? o Same as both single mutants (9:7)  = Complementary gene action  Act in the same pathway, no distinguishable intermediates  Mutations in genes for a target protein and its regular give the same phenotype, as does the double mutant  Same as one single mutant (9:3:4)- genes not alleles o = Recessive epistasis  epi- over stasis- standing  Standing over  Similar in idea to dominance (alleles), but is used for interactions between genes  Same pathway  Cross white (w/w; m+m+) with magenta (w+/w+ ; mm)= blue (w+/w; m+/m)  W is epistatic to m o W  m blue  If you mutate w, no precursor for m to work with, so you get white. o The one that is 4 is the one that is further up in the pathway  Upstream mutants are epistatic to downstream mutants  E gene in dogs if for the pigment being deposited and B is for color o 9 B/_ E/
More Less

Related notes for BIOL 2000

Log In


Join OneClass

Access over 10 million pages of study
documents for 1.3 million courses.

Sign up

Join to view


By registering, I agree to the Terms and Privacy Policies
Already have an account?
Just a few more details

So we can recommend you notes for your school.

Reset Password

Please enter below the email address you registered with and we will send you a link to reset your password.

Add your courses

Get notes from the top students in your class.