Isaac Observed a Sample of Motor Units in Which Single

question 110

Multiple Choice

 Isaac observed a sample of motor units in which single neurons innervated fibers of the same type. This led Isaac to conclude that

• A) neural input probably determines the identity of muscle fibers as slow- or fast-twitch.
• B) the organism that supplied the samples had probably suffered a spinal cord injury.
• C) the organism that supplied the samples was very old.
• D) his sample was not representative, and he needed to obtain more samples before reaching a conclusion.

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Definitions:

Step-Wise Variable Cost

A cost that remains fixed within a certain level of activity but will jump to a higher amount at a certain point due to increased activity.

Variable Costs

Costs that change in proportion to the level of activity or production volume.

Cost-Volume-Profit Analysis

An accounting method used to determine the effects of changes in costs and volume on a company's profits.

Relevant Range

The range of activity within which the assumptions about fixed and variable cost behavior are valid.