What Does Research with Identical Twins on the Role of Heredity

question 128

Multiple Choice

What does research with identical twins on the role of heredity in mental illness indicate?

• A) If one twin is diagnosed as mentally ill, it is inevitable that the second twin will eventually develop the same mental illness.
• B) There is no greater likelihood of the second twin showing mental illness than there would be in any two nontwin siblings.
• C) The second twin has an increased risk of developing the same disorder, but identical twins are usually discordant with respect to mental illness and behavioural disorders.
• D) Mental illness shows almost no evidence of heritability.

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Definitions:

Biological Factors

Components and influences stemming from the biological level, such as genetics, neurochemical imbalances, and brain structure, affecting an individual's health and behavior.

Social Factors

External societal influences that affect an individual's behavior, attitudes, and life chances.

Incentive

A factor, often a reward or punishment, that motivates behavior or increases the likelihood of a certain response.

Biological Needs

Biological needs are the essential requirements that organisms must meet to maintain life, such as food, water, air, and shelter.