Gene S Controls the Sharpness of Spines in a Type

question 26

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. Also, a second gene, N, determines whether or not cactuses have spines. Homozygous recessive nn cactuses have no spines at all. What phenotypes would be expected from a cross between a true-breeding sharp-spined cactus and a spineless cactus?

• 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:

Providing Contact

In psychology, this refers to the act of creating an opportunity for physical or emotional connection between individuals.

Providing Food

The activity or process of supplying or giving food to people or animals.

Providing Movement

Providing movement refers to the process or actions involved in causing or enabling motion or change of position in physical entities or phenomena.

Providing Warmth

Engaging in behaviors that express care, comfort, and emotional support to others.