Topic 10-2

Question 1

a testcross between two genes is called a:

Answer 1

two-point testcross

Question 2

pairs with a frequency of 50% are:

Answer 2

not in the same linkage group

Question 3

when constructing a map with a two point testgroup, you should:

Answer 3

first split genes into linkage groups, then map genes w/in the same linkage groups

Question 4

a three-point testcross is more efficient to map 3 genes as it can be done with:

Answer 4

one cross rather than a series of two-point crosses

Question 5

what are the six major steps of mapping a three point test cross?

Answer 5

1) locate parental phenotypes (non-recombinant progeny)
2) locate the double crossover (rare phenotypes)
3) compare parental phenotypes w/ rare phenotypes
4) fix the genotypes
5) find recombination frequencies
6) put it on a map