Gene S Controls the Sharpness of Spines in a Type

question 60

Multiple Choice

Gene S controls the sharpness of spines in a type of cactus. Cactuses with the dominant allele, S, have sharp spines, whereas homozygous recessive ss cactuses have dull spines. At the same time, a second gene, N, determines whether or not cactuses have spines. Homozygous recessive nn cactuses have no spines at all. A cross between a true-breeding sharp-spined cactus and a spineless cactus would produce ________.

• A) all sharp-spined progeny
• B) 50 percent sharp-spined, 50 percent dull-spined progeny
• C) 25 percent sharp-spined, 50 percent dull-spined, 25 percent spineless progeny
• D) all spineless progeny
• E) It is impossible to determine the phenotypes of the progeny.

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Definitions:

Labor-Market Discrimination

Occurs when two equally qualified individuals are treated differently based on arbitrary characteristics such as race, gender, religion, or nationality in employment decisions.

Compensating Differential

The additional amount of income that a worker requires to be indifferent between working in a job with undesirable conditions and a job with desirable conditions.

Compensating Differential

The difference in wages that arises between jobs with differing levels of risk, convenience, or other non-monetary characteristics, compensating for the less desirable aspects of certain jobs.

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