A Paramecium "Knows" When It Has Encountered a Noxious Substance

question 7

Multiple Choice

A Paramecium "knows" when it has encountered a noxious substance and backs off to veer away.As a one-celled organism,how does it "know" to do this?

• A)The macronucleus has DNA coding that determines this reaction.
• B)The micronucleus is dedicated to controlling just such responses.
• C)This cell is essentially a small neuron,or nerve cell.
• D)This is a rather simple stimulus that changes the electrical potential difference across the cell membrane and depolarization of the membrane results in cilia reversing their direction of beating.
• E)None of the choices is correct.

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Definitions:

Variable Cost

Costs that vary directly with the level of production or volume of services provided.

Composite Units

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