Lab 5 Flashcards
What does crossing over cause
new combinations of alleles
If the parents are AaBb and AaBb what are the gametes
AB,ab,Ab,ab
what does linkage do
allows for cross over
Map distance
distance between 2 genes on a chromosome
How do you know if a gene is linked
recombinant is below 50%
In a diploid plant species, an F1 with the genotype GgLlTt is tested crossed the offspring follow
GgLlTt 621
GgLltt 3
GgllTt 64
Gglltt 109
ggLlTt 103
ggLltt 67
ggllTt 7
gglltt 626
Total 1600
-What is the order of these genes?
-Calculate the recombination fraction between each pair of genes?
-What is the interference value for this data set?
-Explain the meaning of this I Value.
G-T-L
G-T: 0.139 L-T: 0.888
0.49
I indicates the reduction of likelihood a double crossover
A plant of genotype CCdd is crossed to ccDD and F1 test crossed to ccdd. If genes are linked, and 20 cM apart what is the percentage of ccdd recombinants
10%
In Drosophila, 2 genes w and sn are linked and 25 map units apart. Female fly of genotype w+ sn+/w sn crossed to a male from a wild type line. What percent of males be w+ sn?
12.5%
Maize 2 plants heterozygous for recessive alleles a and b are crossed, what frequency of double mutant will appear if a and b are 7.2 mu and both parents carry a and b trans
.001296
A hybrid from and unknown origin is tested crossed and 1,000 progeny resulted 127 red, 153 glossy, 352 wild type, 368 glossy+ red. If glossy and red are recessive what was the parent that was homozygous
glossy red
A hybrid from and unknown origin is tested crossed and 1,000 progeny resulted 127 red, 153 glossy, 352 wild type, 368 glossy+ red. What is your best estimate of map distance between glossy and red in mu
28
a and b are 10 mu, b and c are 20 map units, and a and c are 30 mu . If a triple heterozygote test crossed with 1000 offspring. how many are expected to be double crossover without interference.
20
