If a Fraternal Twin Develops Schizophrenia, the Likelihood of the Other

question 15

Multiple Choice

If a fraternal twin develops schizophrenia, the likelihood of the other twin developing serious mental illness is much lower than with identical twins. This suggests that

• A) schizophrenia is caused by genes.
• B) schizophrenia is influenced by genes.
• C) environment is unimportant in the development of schizophrenia.
• D) identical twins are especially vulnerable to mental disorders.

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Definitions:

Adaptive Functioning

A measure of an individual's social, occupational, and everyday living skills and their ability to meet the demands of personal and community living.

IQ

An intelligence quotient, a total score derived from standardized tests designed to assess human intelligence.

Autism

From the Greek autos, meaning “self”, autism is characterized by difficulty in communicating and forming relationships with other people and in using language and abstract concepts.

Pronoun Reversal

One of the common characteristics of speech in autistic children, in which the child often refers to himself or herself in the third person, perhaps because of trouble shifting reference between speaker and listener or a third party.