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

question 14

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 are correct.

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Definitions:

Market Demand Curve

A graph that shows the relationship between the price of a good and the quantity of that good all consumers are willing to purchase at each price level.

Consumption

The act of using goods and services for personal needs or wants.

Demand Curve

A graphical representation showing the relationship between the price of a good and the amount of it that consumers are willing to purchase at various prices.

Quantity Demanded

The total amount of a good or service consumers are willing and able to purchase at a given price in a specified period.