For a haploid fungus, the starting point in the biosynthesis of the amino acidarginine is Compound X, which is always present in and absorbed from theenvironment. The arginine biosynthetic pathway is:Enzyme AEnzyme BEnzyme ÇCompound XIt is know that genes encoding enzymes A and C are on two differentchromosomes.Compound YCompound Z-ArginineA mutant strain of genotype a (lacking only enzyme A) is crossed to a mutant strainof genotype c (lacking only enzyme C) to generate a diploid strain. Sporulation (i.e.meiosis) is subsequently induced in the resulting diploid strain. What proportion ofthe spores (haploids formed by sporulation) is expected to grow on medium withoutarginine but supplemented with Compound Y?O 100%50%0%25%

Introduction :- Haploid fungus consists of single set of chromosomes . They synthesize amino acid…

For a haploid fungus, the starting point in the biosynthesis of the amino acid arginine is Compound X, which is always present in and absorbed from the environment. The arginine biosynthetic pathway is: Compound X- Enzyme A Compound Y- Enzyme B Enzyme C Compound Z- Arginine It is know that genes encoding enzymes A and C are on two different chromosomes. A mutant strain of genotype a (lacking only enzyme A) is crossed to a mutant strain of genotype c (lacking only enzyme C) to generate a diploid strain. Sporulation (i.e. meiosis) is subsequently induced in the resulting diploid strain. What proportion of the spores (haploids formed by sporulation) is expected to grow on medium without arginine but supplemented with Compound Y? 100% 50% S 0% 25%

For a haploid fungus, the starting point in the biosynthesis of the amino acid arginine is Compound X, which is always present in and absorbed from the environment. The arginine biosynthetic pathway is: Compound X- Enzyme A Compound Y- Enzyme B Enzyme C Compound Z- Arginine It is know that genes encoding enzymes A and C are on two different chromosomes. A mutant strain of genotype a (lacking only enzyme A) is crossed to a mutant strain of genotype c (lacking only enzyme C) to generate a diploid strain. Sporulation (i.e. meiosis) is subsequently induced in the resulting diploid strain. What proportion of the spores (haploids formed by sporulation) is expected to grow on medium without arginine but supplemented with Compound Y? 100% 50% S 0% 25%

Concepts of Biology

1st Edition

ISBN:9781938168116

Author:Samantha Fowler, Rebecca Roush, James Wise

Publisher:Samantha Fowler, Rebecca Roush, James Wise

Chapter7: The Cellular Basis Of Inheritance

Section: Chapter Questions

Problem 1ACQ: Figure 7.2 If a mutation occurs so that a fungus is no longer able to produce a minus mating type,...

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