GATE XL · 2019 · XL-T
Question 20: Genetics
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Question 20
XL-TNAT2 marksNeeds review
A genetic cross was made between homozygous wild-type males (a⁺b⁺c⁺) and triple-mutant females (abc) of Drosophila melanogaster. Then the F₁ males (a⁺b⁺c⁺) were back crossed to the triple-mutant females which resulted in the following F₂ progenies:
Progeny | Number |
|---|---|
a⁺bc | 16 |
ab⁺c | 115 |
abc | 311 |
a⁺b⁺c | 64 |
ab⁺c⁺ | 61 |
a⁺b⁺c⁺ | 317 |
a⁺bc⁺ | 99 |
ab c⁺ | 17 |
Total | 1000 |
The order of genes as determined from the above data was found to be “b a c” (note that the order is equivalent to “c a b” and the order of outside markers are arbitrary).
The map distance between “b and c” is _____ centiMorgan (round off to 1 decimal place).
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2019XL-T
GATE XL 2019 · Paper 1
Life Sciences · Original paper archive
- Section
- Section XL-T
- Question type
- Numerical answer (NAT)
- Marks
- 2 marks
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