Many Soldiers Returning from the War in Iraq Have Suffered

question 32

Multiple Choice

Many soldiers returning from the war in Iraq have suffered from post-traumatic stress disorder (PTSD) . However, your friend from high school who has returned from a protracted active deployment seems to be coping well even though he had some truly horrible experiences. How might you explain this with regard to the biological and environmental contributions to behaviour?

• A) He may not have a genetic susceptibility to PTSD.
• B) Environment isn't an important factor in determining behaviour.
• C) He inherited a genetic predisposition to PTSD.
• D) The experiences really are not as bad as people say.

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Definitions:

Hardy-Weinberg Equilibrium

A principle stating that allele and genotype frequencies in a population will remain constant from generation to generation in the absence of evolutionary influences.

Stabilizing Selection

Outcome of natural selection in which extreme phenotypes are eliminated and the average phenotype is conserved.

Intermediate Phenotype

An intermediate phenotype exhibits characteristics that are between two extremes of a trait, often seen in heterozygotes in incomplete dominance genetic patterns.

Reproductive Success

The success an individual has in passing its genes to the next generation, often measured by the number of offspring that survive to reproduce.