An Identifier Is an Attribute or a Group of Attributes

question 20

True/False

An identifier is an attribute or a group of attributes whose value is associated with one and only one entity instance.

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Definitions:

Hybrid Inviability

A postzygotic reproductive isolating mechanism in which the embryonic development of an interspecific hybrid is aborted.

Mutation

A change in the DNA sequence within an organism's gene or chromosome, leading to variations in trait expression and possibly to different phenotypes.

Habitat Isolation

A type of prezygotic barrier where two species that could interbreed do not, because they inhabit different habitats and rarely encounter each other.

Environmental Isolation

The separation of population groups by physical barriers or distances, leading to genetic divergence and potentially speciation.