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:

Discount Rate

The interest rate used to discount future cash flows of a financial instrument to present value, reflecting the time value of money.

Present Value

The present value is the present-day valuation of a future money sum or cash flow series, determined by a given rate of return.

Simple Interest

A method of calculating the interest charge on a loan or financial product based on the original principal amount and the rate of interest over a specific time period, without compounding.

Interest on Interest

Earnings from reinvesting the interest received from an investment, leading to exponential growth over time.