Studies of Phenylketonuria (PKU) Provide Particularly Strong Evidence for the Conclusion

question 69

Multiple Choice

Studies of phenylketonuria (PKU) provide particularly strong evidence for the conclusion that

• A) when some people fail to use some ability, that ability grows weaker and weaker in later generations.
• B) X-linked recessive genes express their effects more strongly in males than they do in females.
• C) all mammals are descended from a common ancestor.
• D) changes in the environment can alter the outcome of a condition that is under genetic control.

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Definitions:

Specific Stimulus

A particular environmental factor or event that elicits a specific response from an organism.

Spontaneous Recovery

The reappearance of a previously extinguished conditioned response after a pause.

Drug Cravings

Intense desires or urges for the repeated use of substances despite potential negative consequences.

Documentary

A non-fictional film or television show that provides a factual report on a particular subject, often with the goal of informing or educating the audience.