Gene S Controls the Sharpness of Spines in a Type

question 27

Multiple Choice

Gene S controls the sharpness of spines in a type of cactus. Cacti with the dominant allele, S, have sharp spines, whereas homozygous recessive ss cacti 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% sharp-spined, 50% dull-spined progeny
• C) 25% sharp-spined, 50% dull-spined, 25% spineless progeny
• D) It is impossible to determine the phenotypes of the progeny.

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Definitions:

Theocratic

Pertaining to a form of government in which a deity is recognized as the supreme civil ruler, with the deity's laws being interpreted by ecclesiastical authorities.

Anarchic

Lacking order, governance, or authoritative structure, often resulting in chaos or disorder.

Republic

A form of government in which the country is considered a "public matter" with officials elected by the people.

Democratic

Pertaining to a form of government in which the people have the power to choose their governing legislation.