Refer to the Figure

question 10

Multiple Choice

Refer to the figure.
Medicago truncatula, or barrelclover, is a clover-like legume that has a mutualistic association with mycorrhizal fungi. In the experiment illustrated in the figure, fungi in contact with Medicago had access to either no phosphorus, or to either 35 or 700 ?M of phosphorus. According to the figure, how did Medicago alter the amount of carbohydrate it transferred to the fungi in response to the change in fungal phosphorus levels?

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Definitions:

Skinner Box

An experimental apparatus designed by B.F. Skinner for studying animal behavior through operant conditioning.

Reinforcer

Any stimulus that strengthens or increases the likelihood of a specific response or behavior by being presented immediately after that response or behavior.

Respondent Behavior

behavior that occurs as a direct response to a specific stimulus, often without conscious decision, in classical conditioning.

Superstitious Behavior

Actions based on irrational beliefs that certain actions or events can influence outcomes in a way not justified by reason or science.