Ch 7 – Linkage.docx

4 Pages
69 Views
Unlock Document

Department
Biological Sciences Program
Course
BSCI 222
Professor
Dr.Straney
Semester
Spring

Description
Ch 7 – Linkage, Recombination, Eukaryotic Gene Mapping 02/25/2014 7.1 – Linked Genes Do Not Assort Independently linked genes – genes that are located close together on the same chromosome and belong to the same  linkage group not expected to assort independently 7.2 – Linked Genes Segregate Together and Crossing Over Produces Recombination Between Them genes that are close together on the same chromosome are inherited together crossing over results in recombination linkage and crossing over are like opposites – linkage keeps things together and crossing over mixes them  up Complete Linkage Compared with Independent Assortment Test cross reveals the effects of linkage With complete linkage, only nonrecombinant progeny are produced With independent assortment, half the progeny are recombinant and half the progeny are not Nonrecombinant gametes – gametes that only contain original combinations of alleles present in  the parents Recombinant gametes – gametes with new combos of alleles Crossing Over with Linked Genes Theory:  For each meiosis in which a single crossover takes place, two nonrecombinant and two recombinant  gametes will be produced.  For closely linked genes, crossing over doesn’t take place in every meiosis.  If there is a single crossover, half the gametes are recombo and half are nonrecombo.  So the total percentage of recombo’s is always half the percentage of meiosis in which crossing over takes  place.  Calculating Recombination Frequency ( # of recombinant progeny / total # of progeny ) x 100 Coupling and Repulsion Coupling 
More Less

Related notes for BSCI 222

Log In


OR

Join OneClass

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

Sign up

Join to view


OR

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.


Submit