A City Was Intensively Sprayed with DDT to Control Houseflies

question 44

Multiple Choice

A city was intensively sprayed with DDT to control houseflies. The number of houseflies was immediately greatly reduced. Each year thereafter, the city was sprayed again, but the flies gradually increased in numbers until 10 years later, when they were almost as abundant as they were when the control program began. Which explanation applies to this situation?

• A) Flies from other areas moved in and replaced the ones killed by DDT.
• B) The few flies that were affected by DDT but survived developed antibodies to DDT, which they passed on to their descendants.
• C) The DDT caused new mutations to occur in the surviving flies, resulting in resistance to DDT.
• D) The DDT killed most flies. The few that were already naturally resistant survived and passed this resistance on to their offspring.

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Definitions:

Encoding Problems

Difficulties in converting information into a form that can be stored and retrieved from memory, often affecting learning and retention.

Flashbulb Memory

A vivid, detailed memory of an emotionally significant moment or event.

Eidetic Image

An unusually vivid and detailed mental image that retains visual details, often referred to as a "photographic memory."

Semantic Memory

A component of long-term memory that involves the recollection of factual information, concepts, and ideas not linked to personal experience.