Refer to the Figure, Which Shows a Fungal Interaction with a Photosynthetic

question 29

Multiple Choice

Refer to the figure, which shows a fungal interaction with a photosynthetic cell. Which statement is not a potential explanation for the scenario shown?

• A) The fungus and photosynthetic cell have joined together in a symbiotic association to form a lichen.
• B) The fungus has formed haustoria that push directly against the plant plasma membrane in order to absorb nutrients secreted from the plant cell.
• C) The fungal hyphae are ectomycorrhizae and have entered the plant cell in order to provide nitrogen in exchange for carbon compounds.
• D) A parasitic fungus has entered a leaf through a stoma and is leaching nutrients from the plant cells through specialized structures that form from its hyphae.
• E) The fungal hyphae are part of an arbuscular mycorrhizal network in which the fungus provides phosphorus to the plant in exchange for carbon compounds.

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Definitions:

Fixed Interval Schedule

A type of conditioning schedule where a reward or reinforcement is administered after a set period of time has passed, assuming the required response has been made.

Continuous Reinforcement

A method of learning that involves giving a reward after every correct response in order to reinforce the desired behavior.

Secondary Reinforcement

A stimulus that becomes reinforcing through its association with a primary reinforcer.

Intermittent Reinforcement

A conditioning schedule in which a reward or punishment is given only some of the time a behavior occurs, leading to more robust responses.