When Identical Twins Differ in Phenotype of a Complex Trait

question 106

Multiple Choice

When identical twins differ in phenotype of a complex trait, it is almost always due to:

• A)mutation.
• B)segregation.
• C)epistasis.
• D)genotype-by-environment interaction.
• E)the environment.

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Definitions:

Basic Emotions

Those core affects that have old neurobiological underpinnings. According to Izard, they include joy/happiness, interest, sadness, anger, disgust, and fear.

Expressive Behaviors

Actions or gestures that convey emotions, feelings, or attitudes without the use of verbal communication.

Joy/Happiness

A state of well-being and contentment characterized by feelings of pleasure and satisfaction.

Reactive, Difficult Infants

Infants who are particularly likely to react negatively to new situations or stimuli and are generally more challenging to soothe or calm.