Linkage Studies Have Narrowed the Search for a Genetic Contribution

question 129

Multiple Choice

Linkage studies have narrowed the search for a genetic contribution to mood disorders by

• A) establishing the need for longitudinal research on monozygotic twins who have been separated at birth.
• B) pointing to gene combinations that appear in family members who have had symptoms of major depression.
• C) identifying genes for which there is no link to mood disorders.
• D) searching particular areas on a chromosome or several chromosomes that have a likelihood of containing risk genes.

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Definitions:

Reserves of a Mineral

Quantities of a mineral that are known to exist with a reasonable degree of certainty and can be recovered economically with the existing technology under current economic conditions.

Earth's Innermost Zone

The Earth's core, which is the central part of the Earth below the mantle, consisting of a solid inner core and a fluid outer core primarily made of iron and nickel.

Smelting

The process of extracting a metal from its ore by heating and melting, often using a chemical reducing agent.

Ore Mineral

Naturally occurring minerals from which metals or minerals of economic value can be extracted profitably.