Snails Typically Avoid Sunlit Areas,but Some Snails Infected with Certain

question 20

Multiple Choice

Snails typically avoid sunlit areas,but some snails infected with certain parasites become attracted to light and prefer sunlit areas.Which of the following is the most likely hypothesis given the life cycles of many parasites?

• A)The parasite itself must be exposed to light in order to survive in the snail.
• B)The parasite manipulates the behavior of the snail so that it gets eaten more readily,which allows the parasite to complete its life cycle.
• C)The snail is behaving differently in order to rid itself of the parasite.
• D)The snail is dying from the parasite and is therefore looking for the light.
• E)The parasite must exit the snail in a sunlit area in order to move and find its next host.

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Definitions:

Salient

Something that stands out conspicuously or is most noticeable or important.

Preceding

Occurring or coming before something else in time or order.

Rats

Rodents that are often used in research as a model organism to study behavior, disease, and genetics.

Schedule-induced Polydipsia

An abnormal increase in drinking behavior that is observed in animals subjected to certain intermittent or unpredictable schedules of reinforcement, not directly related to the physiological demands for water.