please explain your reasons for the correct answer.
4. Drosophila have two genes y (yellow body) and car (carnationeyes). Doubly heterozygous females (y+ car+/y car) are mated tohemizyogous recessive males, and 50% percentage of the male progenyfrom such a female are be recombinant for y and car. Which of thefollowing statements is correct?
A. y and car are the same chromosome and 50 m.u. apart
B. y and car are the same chromosome and more than 50 m.u.apart.
C. y and car are on different chromosomes.
D. y and car are on different chromosomes or are on the samechromosome and more than 50 m.u. apart.
E. none of the above are correct.
5) If I tell you that genes A and B are on the same chromosome and70 map units apart, how did I determine this?
A) I did a cross and got 70% recombination between the twogenes
B) I did a cross and got 35% recombination between the twogenes
C) I did a cross and got 70% gene conversions
D) I did a cross and genes A and B showed both 35% recombinationwith gene C.
E) None of the above are correct.
4. Drosophila have two genes y (yellow body) and car (carnationeyes). Doubly heterozygous females (y+ car+/y car) are mated tohemizyogous recessive males, and 50% percentage of the male progenyfrom such a female are be recombinant for y and car. Which of thefollowing statements is correct?
A. y and car are the same chromosome and 50 m.u. apart
B. y and car are the same chromosome and more than 50 m.u.apart.
C. y and car are on different chromosomes.
D. y and car are on different chromosomes or are on the samechromosome and more than 50 m.u. apart.
E. none of the above are correct.
5) If I tell you that genes A and B are on the same chromosome and70 map units apart, how did I determine this?
A) I did a cross and got 70% recombination between the twogenes
B) I did a cross and got 35% recombination between the twogenes
C) I did a cross and got 70% gene conversions
D) I did a cross and genes A and B showed both 35% recombinationwith gene C.
E) None of the above are correct.
Related textbook solutions
Related questions
Which of these statements is incorrect?
Syntenic genes are located on the same chromosome. |
Independent assortment results in recombinant chromosomes. |
You can reliably predict the relative genetic distance fromgenesâ physical distance on a chromosome. |
Linked genes are always syntenic. |
What is the relative genetic distance between two linked genesif the recombination frequency is 0.49?
0.49 cM |
4.9 cM |
49 cM |
490 cM |
What statement best explains the distortion in Mendelian ratiosobserved by Bateson & Punnett in 1905? (Reminder: they found anoverrepresentation of F2 offspring showing both dominant orrecessive phenotypes, and an underrepresentation of offspringdisplaying one dominant and one recessive phenotype)
| Human error: they should have been more careful about theirexperimental setup. |
| Gene linkage: Genes for flower color and pollen shape arephysically close on the same chromosome, leading to a breakdown inthe independent assortment of the alleles for these traits. |
| Chromosome crossover: Homologous recombination of twochromatids during meiosis caused the alleles to shuffle, resultingin a breakdown of the independent assortment of the alleles forthose genes. |
Random variation: No two situations are alike. In finitepopulations, you are going to get some variation across a mean. |
When determining the relative genetic distance between twogenes, why is dihybrid back-cross preferable over traditionaldihybrid cross?
| 9:3:3:1 phenotypic ratio is easier to work with than 1:1:1:1ratio. |
| Genotypes of the offspring can be determined based on theirphenotype. |
If the genes are independently assorted, the dihybrid back-crosswould result in only 2 genotypes in the F1 generation. |
B and C |
Why do we map genes?
| To understand how genes interact with each other |
| Comparative genomics analysis |
| To determine the genotype of an organism |
| All of the above |
