The Map Distances for Four Linked Genes Are as Follows

question 47

Multiple Choice

The map distances for four linked genes are as follows: A is 22 cM from B, B is 7 cM from C, C is 9 cM from D, B is 2 cM from D, A is 20 cM from D, and A is 29 cM from C. Based on these data, what is the order of these four genes on the chromosome?

• A) ABCD
• B) ADBC
• C) ABDC
• D) BADC
• E) CADB

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Definitions:

Autosomes

In humans, the 22 pairs of chromosomes not related to sexual expression.

Zygotes

The initial cell formed when a sperm cell fertilizes an egg cell, marking the beginning of pregnancy.

Gametes

The reproductive cells (sperm in males and ova in females) that contain half the genetic information of the organism, essential for sexual reproduction.

Sexual Differentiation

The process by which the sexual organs develop during the prenatal period, leading to the development of sex differences in the body.