In the yeast cross of ade2 met14 his3 x + + +, a total of 120 tetrads are analyzed. The following tetrad types are found in the numbers shown below each tetrad. The markers ade2, met14, and his3 are abbreviated a, m, and h and the wild type allele of each gene is indicated by +.

 

Use this categorization and the numbers of each type to determine which (if any) of the three markers are linked. For any linked markers, calculate the distance between them in cM.      

To measure the distance between two linked His– mutations, you cross a his2– mutant to a his4– mutant and then dissect 100 tetrads. Your lab partner records which spore clones are His+ and which are His– ; but then the fool loses the papers on which most of the data is recorded. In the end all he can remember is that there were three different tetrad types an that there was only one tetrad of the type with 2 His+ and 2 His– spore clones.

#Question id: 4737

#Unit 8. Inheritance Biology

Two independent pure line varieties having white and green phenotype in their fruit were cross, the all f1 progeny is white fruit. The F2 progeny obtain from selfing show white, yellow and green in ratio of 12:3:1. Which of the following is correct?

#Question id: 4738

#Unit 8. Inheritance Biology

Red kernel color in wheat results from the presence of at least one dominant allele of each of two independently segregating genes . Kernels on rr bb plants are white, and the genotypes R— bb and rr B— result in brown kernel color. Suppose that plants of a variety that is true breeding for red kernels are crossed with plants true breeding for white kernels produced F1 were allowed to selfing .what are F2 phenotype ratio ?

#Question id: 4739

#Unit 8. Inheritance Biology

Inheritance of leaf variegation in the four-o’clock plant, Mirabilis jalapa. the leaves and shoots of one variety of four-o’clock were variegated, displaying a mixture of green and white splotches. If  Flowers on the variegated branches gave rise to

#Question id: 4740

#Unit 8. Inheritance Biology

Following metabolic pathway for synthesis of anthocyanin product ? Which of the following cross produced all purple phenotype in their progeny ?

#Question id: 4741

#Unit 8. Inheritance Biology

The F2 progeny from a particular cross exhibit a modified dihybrid ratio of 9 : 7 (instead of 9 : 3 : 3 : 1). What phenotypic ratio would be expected from a testcross of the F1?

#Question id: 4742

#Unit 8. Inheritance Biology

In birds, sex is determined by a ZW chromosome scheme. Males are ZZ and females are ZW. A recessive lethal allele that causes death of the embryo is sometimes present on the Z chromosome in pigeons. What would be the sex ratio in the offspring of a cross between a male that is heterozygous for the lethal allele and a normal female?