In hyenas, long manes (a) are recessive to short manes (A) and having round ears (b) is recessive to having pointy ears (B). A hyena with a long mane that is homozygous for pointy ears is crossed with a hyena that has round ears and is homozygous for a short mane. The F1 progeny are then crossed with hyenas that have long manes and round ears (a testcross). PART A. If the loci for mane length and ear shape are on different chromosomes, what ratio would you expect from the testcross? PART B. Let's say instead that the genes for mane length and ear shape are located on the same chromosome, and findings from mapping experiments indicate that they are 16 m.u. apart. Assume 180 offspring are produced in testcrosses, what is the number of progeny expected for each phenotypic class? PART C. Is the F1 progeny in coupling or repulsion? Explain. Give the genotype of the F1 progeny of the parental cross, using notation that shows linkage.

In hyenas, long manes (a) are recessive to short manes (A) and having round ears (b) is recessive to having pointy ears (B). A hyena with a long mane that is homozygous for pointy ears is crossed with a hyena that has round ears and is homozygous for a short mane. The F1 progeny are then crossed with hyenas that have long manes and round ears (a testcross). PART A. If the loci for mane length and ear shape are on different chromosomes, what ratio would you expect from the testcross? PART B. Let's say instead that the genes for mane length and ear shape are located on the same chromosome, and findings from mapping experiments indicate that they are 16 m.u. apart. Assume 180 offspring are produced in testcrosses, what is the number of progeny expected for each phenotypic class? PART C. Is the F1 progeny in coupling or repulsion? Explain. Give the genotype of the F1 progeny of the parental cross, using notation that shows linkage.

Concepts of Biology

1st Edition

ISBN:9781938168116

Author:Samantha Fowler, Rebecca Roush, James Wise

Publisher:Samantha Fowler, Rebecca Roush, James Wise

Chapter8: Patterns Of Inheritance

Section: Chapter Questions

Problem 5RQ: Imagine that you are performing a cross involving seed texture in garden pea plants. You cross...

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