Question

Question 5 In Drosophila, ebony body (e) and rough eyes (r) are encoded by linked autosomal recessive genes on the third chro
0 0
Add a comment Improve this question Transcribed image text
Answer #1

ebony and rough eyes are closely linked to each other so that recombination does not occur between genes.

let the alleles be e+ - wildtype body e- ebony body

r+ - wildtype eyes, r- rough eyes

given that these genes are located on autosomes, so

genotype of the homozygous ebony female: eer+r+

genotype of homozygous rough eyed male: e+e+rr

eer+r+ * e+e+rr

er+/e+r

since these genes are linked closely to each other such that recombination does not occur between these genes, so er+/e+r can produce only two types of gametes er+ and e+r. gametes have the same combination of alleles as the chromosomes, one chromosome has e and r+ alleles and other chromosome has e+ and r alleles so it produces er+ and e+r gametes.

F1 females are crossed to ebony, rough males, the genotype of ebony rough males is eerr, it can produce only one type of gamete er.

er+/e+r * eerr

er+ e+r
er er+/er ( ebony body) e+r/er (rough eyes)

so half of the progenies have ebony body and the other half have rough eyes. that is 50% of progeny have ebony body and 50 of progeny have rough eyes.

so the answer is d) ebony 50%, rough 50%, wildtype 0%, rough, ebony 0%.

Add a comment
Know the answer?
Add Answer to:
Question 5 In Drosophila, ebony body (e) and rough eyes (r) are encoded by linked autosomal...
Your Answer:

Post as a guest

Your Name:

What's your source?

Earn Coins

Coins can be redeemed for fabulous gifts.

Not the answer you're looking for? Ask your own homework help question. Our experts will answer your question WITHIN MINUTES for Free.
Similar Homework Help Questions
  • Cinnabar eyes (cn) and reduced bristles (rd) are autosomal recessive characters in Drosophila. A homozygous wild-type...

    Cinnabar eyes (cn) and reduced bristles (rd) are autosomal recessive characters in Drosophila. A homozygous wild-type female was crossed to a reduced, cinnabar male, and the F1 males were then crossed to the F1 females to obtain the F2. Of the 400 F2 offspring obtained, 292 were wild type, 9 were cinnabar, 7 were reduced, and 92 were reduced and cinnabar.

  • In Drosophila, the autosomal recessive brown eye color mutation (b) displays interactions with both the X-linked...

    In Drosophila, the autosomal recessive brown eye color mutation (b) displays interactions with both the X-linked recessive vermilion mutation (v) and the autosomal recessive scarlet (s) mutation. Flies homozygous for brown and simultaneously hemizygous or homozygous for vermilion have white eyes. Flies simultaneously homozygous for both the brown and scarlet mutations also have white eyes. Flies that are wildtype at all 3 loci have wildtype eye color. Flies that are homozygous or hemizygous for the recessive mutant at only one...

  • 37) The genes for mahogany eyes and ebony body are chromosome III in Drosophila. Assume that...

    37) The genes for mahogany eyes and ebony body are chromosome III in Drosophila. Assume that a mahogany-eyed female was mated to an ebony-bodied male and that the resulting F1 phenotypically wild-type females were mated to mahogany, ebony males. Of 1000 offspring, 325 were mahogany, 375 were ebony, 125 were wild type, and 125 were both mahogany and ebony. What is the distance between the mahogany and ebony genes? A) 50 CM B) 15 CM C) 25 CM D) 75...

  • In Drosophila melanogaster, the recessive X-linked alleles white (w), miniature (m) and forked (f) give the...

    In Drosophila melanogaster, the recessive X-linked alleles white (w), miniature (m) and forked (f) give the phenotypes white eyes, miniature wings and forked brushes. The recombination between the w and m loci is 35%, and between the m and f loci, 20%. Wild-type males were crossed with females from a strain that was homozygous recessive for the three alleles, then the F1 flies were sibling mated. What phenotype frequencies are expected in F2 a) if there is no interference, and...

  • Obj. 37. In Drosophila forked (F) bristles is X-linked and dominant. If a virgin female homozygous...

    Obj. 37. In Drosophila forked (F) bristles is X-linked and dominant. If a virgin female homozygous for forked s crossed with a wild-type male predict; the proportions/ratios of genotypes and phenotypes among the F1 and F2 as the sex and bristle trait. F: Females Phenotype F1 Males Phenotype Genotype Genotype F2 Females Phenotype = F2 Males Phenotype Genotype = Genotype =

  • EXTRA CREDIT (10 pts) 7) In Drosophila, white eye is an X-linked recessive trait and ebony...

    EXTRA CREDIT (10 pts) 7) In Drosophila, white eye is an X-linked recessive trait and ebony body is an autosomal recessive trait. A homozygous white-eyed female (normal body) is crossed with a homozygous ebony male (normal, red eyes). a) What phenotypic ratio do you expect in the F1 generation? Show your work. b) What phenotypic ratio do you expect in the F2 generation? Show your work.

  • In Drosophila, the X-linked recessive mutation vermillion (v) causes bright red eyes, in contrast to the...

    In Drosophila, the X-linked recessive mutation vermillion (v) causes bright red eyes, in contrast to the brick-red eyes caused by the wild-type allele. A separate autosomal recessive mutation, brown (bw), causes flies to have brown eyes. Flies carrying both mutations have no eye pigmentation and are white-eyed. Determine the F1 and F2 phenotypic ratios for each sex from the following crosses: (a) brown females X vermillion males (b) white-eyed females X wild-type males

  • Scalloped (sd) wing is an X-linked recessive and ebony (e) body color is an autosomal recessive...

    Scalloped (sd) wing is an X-linked recessive and ebony (e) body color is an autosomal recessive mutation in Drosophila. If a true breeding scalloped female that is wild type for ebony, is mated with a true breeding ebony male that is wild type for scolloped, what proportion of scalloped, normal body colored males is expected in the F2? a. 0 b. 1/16 c. 3/16 d. 1/32 e. 1/8

  • You cross a Drosophila female with kidney-shaped and brown eyes with a male that has wildtype...

    You cross a Drosophila female with kidney-shaped and brown eyes with a male that has wildtype eye shape and color. Kidney-shaped eyes are found in females that are heterozygous for the bar eyed mutation. Bar eyed females are homozygous for the bar eyed mutant allele, whereas bar eyed males are hemizygous for the mutation. Brown eyes are an autosomal recessive mutation. Attention: Half of the resulting F1 has brown eyes! Would you expect to see bar eyed females in the...

  • You cross a Drosophila female with kidney-shaped and brown eyes with a male that has wildtype...

    You cross a Drosophila female with kidney-shaped and brown eyes with a male that has wildtype eye shape and color. Kidney-shaped eyes are found in females that are heterozygous for the bar eyed mutation. Bar eyed females are homozygous for the bar eyed mutant allele, whereas bar eyed males are hemizygous for the mutation. Brown eyes are an autosomal recessive mutation. Attention: Half of the resulting F1 has brown eyes! Would you expect to see bar eyed females in the...

ADVERTISEMENT
Free Homework Help App
Download From Google Play
Scan Your Homework
to Get Instant Free Answers
Need Online Homework Help?
Ask a Question
Get Answers For Free
Most questions answered within 3 hours.
ADVERTISEMENT
ADVERTISEMENT
ADVERTISEMENT