Gene S Controls the Sharpness of Spines in a Type

question 12

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. A second gene, N, determines whether or not cacti have spines. Homozygous recessive nn cacti have no spines at all. If cacti heterozygous for both traits, SsNn, were allowed to self-pollinate, the offspring would segregate into which of the following phenotype ratios?

• A) 3 sharp-spined:1 spineless
• B) 1 sharp-spined:2 dull-spined:1 spineless
• C) 1 sharp-spined:1 dull-spined:1 spineless
• D) 9 sharp-spined:3 dull-spined:4 spineless

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Definitions:

Activity Levels

The volume of production or the level of sales activity within a company, which can affect various costs and pricing strategies.

High-low Method

An accounting technique used to estimate variable and fixed costs by analyzing the lowest and highest levels of activity and their associated costs.

Mixed Cost

An expense that contains both fixed and variable components, changing in total with the level of activity but not in a directly proportional manner.

High-low Method

A method employed in accounting that calculates variable and fixed expenses by analyzing the maximum and minimum activity levels.