Gene Linkage and Mapping Chromosomes

Question 1

What did Thomas Morgan cross
What happened in the F1 and F2 generations?

Answer 1

-AABB (wild body straight winds) x aabb (black body curved wings)
-F1 produced the expected AaBb (wild body straight wings)
-F2 did not produce the 9331 ratio

Question 2

-what did genes on non homologous chromosomes do?
-since body colour and wing shape didnt segregate indepdendently, what did that mean?
-what are linked genes

Answer 2

-seperate and segregate indepdendently
-they were on the same chromosome
-genes on the same chromosome

Question 3

what are unexpected genes called that form as a result of crossing over?
-crossover % formula
-what must be used to determine the # of recombinants

Answer 3

-recombinants
-# of recombinants/total # of offspring
-the F1 AaBb x tester aabb

Question 4

What happens to genes near each other?
what happens to genes with distance between them?
-small vs large crossover %

Answer 4

-they end up on the same chromosome
-end up on different chromosomes and cross over
-small % means that they’re close, large means theres distance

Question 5

The greater the crossover %, the greater the _______ ________.
-what is map distance

Answer 5

map distance
-distance between genes on a chromosome