In mice, dwarfism is caused by an X-linked recessive allele, and pink coat is caused by an autosomal dominantallele (coats are normally brownish). If a dwarf femalefrom a pure line is crossed with a pink male from a pureline, what will be the phenotypic ratios in the F1 and F2 ineach sex? (Invent and define your own gene symbols.)

In mice, dwarfism is caused by an X-linked recessive allele, and pink coat is caused by an autosomal dominantallele (coats are normally brownish). If a dwarf femalefrom a pure line is crossed with a pink male from a pureline, what will be the phenotypic ratios in the F1 and F2 ineach sex? (Invent and define your own gene symbols.)

BIOLOGY:CONCEPTS+APPL.(LOOSELEAF)

10th Edition

ISBN:9781305967359

Author:STARR

Publisher:STARR

Chapter14: Human Inheritance

Section: Chapter Questions

Problem 2GP: Human females have two X chromosomes XX; males have one X and one Y chromosome XY. a. With respect...

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Human sex chromosomes are XX for females and XY for males. a. With respect to an X-linked gene, how many different types of gametes can a male produce? b. If a female is homozygous for an X-linked allele, how many different types of gametes can she produce with respect to this allele? c. If a female is heterozygous for an X-linked allele, how many different types of gametes can she produce with respect to this allele?
Human females have two X chromosomes XX; males have one X and one Y chromosome XY. a. With respect to X-linked alleles, how many different types of gametes can a male produce? b. A female homozygous for an X-linked allele can produce how many types of gametes with respect to that allele? c. A female heterozygous for an X-linked allele can produce how many types of gametes with respect to that allele?
An allele in Drosophila produces a “star-eye” trait in the heterozygousindividual. (It is not X-linked.) However, the star-eye allele is lethal in homozygotes. What would be the ratio and phenotypesof surviving flies if star-eyed flies were crossed to each other?
IN DROSOPHILA, AN X-LINKED RECESSIVE MUTATION, Xm CAUSES MINIATURE WINGS. LIST THE F₂ PHENOTYPIC RATIOS IF: A MINIATURE-WINGED FEMALE IS CROSSED WITH A NORMAL MALE AND A MINIATURE-WINGED MALE IS ● ● CROSSED WITH A NORMAL FEMALE. WHAT WOULD THE PHENOTYPIC RATIO FROM (A) BE IF THE MINIATURE- WINGED GENE WERE AUTOSOMAL? ASSUME IN ALL CASES THAT THE P1 INDIVIDUALS ARE TRUE-BREEDING.
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