In Drosophila, the Genes Y, F, and V Are All

question 36

Multiple Choice

In Drosophila, the genes y, f, and v are all X-linked. Females who are homozygous for recessive alleles of all three genes (y f v / y f v) are crossed to wild-type males. The resulting trihybrid F1 females are testcrossed. The F2 are distributed as follows:

$$\begin{array} { | l | r | } \hline y f v & 3210 \\\hline y f v ^ { + } & 72 \\\hline y f ^ { + } v & 1024 \\\hline y f ^ { + } v^ + & 678 \\\hline y ^ { + } f v & 690 \\\hline y ^ { + } f v ^+ & 1044 \\\hline y ^ { + } f ^+ v & 60 \\\hline y ^ { + } f ^+ v^ + & 3222 \\\hline & 10,000 \\\hline\end{array}$$

-Which of the following linkage maps correctly shows the order and distance between the y, f, and v genes?

• A)f--35 m.u.--y--15 m.u.--v
• B)f--22 m.u.--y--15 m.u.--v
• C)y--35 m.u.--f--22 m.u.--v
• D)y--22 m.u.--v--15 m.u.--f
• E)y--15 m.u.--v--22 m.u.--f

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Definitions:

Direct Labour

The wages and other compensation paid to employees who are directly involved in producing goods or providing services.

Labour Rate Variance

The difference between the actual cost of labor and the expected (or standard) cost of labor for the actual production level.

Labour Efficiency Variance

A measure used in accounting to indicate the difference between the actual number of labor hours used and the standard number of hours that should have been used, multiplied by the standard labor rate.

Variable Overhead

Costs that vary with the level of production or business activity, such as utilities and indirect materials, but do not directly correlate to direct labor or materials.