Use the Following to Answer Questions

question 6

Multiple Choice

Use the following to answer questions
Scenario I
The following scenario presents fabricated data consistent with the results of the following study:
Gilbertson,M.W. ,Shenton,M.E. ,Ciszewski,A. ,Kasai,K. ,Lasko,N .B. ,Orr,S.P. ,& Pitman,R.K.(2002) .Smaller hippocampal volume predicts pathologic vulnerability to psychological trauma.Nature Neuroscience,5,1242-1247.
Persons who live through a traumatic experience may develop posttraumatic stress disorder (PTSD) .PTSD is characterized by chronic physiological arousal,recurrent unwanted thoughts or images,and avoidance of things that bring the trauma to mind,with symptoms persisting for more than 1 month.Persons with PTSD also are at risk for other psychological disorders,with substance abuse disorder being a common comorbid diagnosis.In the last two decades,a number of studies have demonstrated that persons with PTSD have smaller hippocampi than controls.This may result from the neurotoxic effects of stress hormones examined the hippocampal volume of combat veterans with and without PTSD who each had an identical twin who never served in the military.Fabricated results consistent with this study are shown in Figure 15.1.
Figure 15.1
-(Scenario I) The purpose of studying monozygotic twins of combat veterans in the Gilbertson and colleagues (2002) study was to:

• A)demonstrate that combat exposure causes PTSD.
• B)demonstrate that combat exposure is associated with PTSD.
• C)determine if smaller hippocampi are the causes or consequences of PTSD.
• D)control for all other third variables related to genetics other than hippocampal volume.

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Definitions:

Geometric Isomers

Molecules with the same formula and sequence of bonded atoms, but differing in the three-dimensional orientations of their atoms in space.

Structural Isomers

Molecules with the same molecular formula but different arrangements of atoms, resulting in different properties.

Valence Electrons

The electrons in the outermost shell of an atom, which determine the atom's chemical properties and its ability to form bonds.

Hydrogen Bonds

Weak bonds between a hydrogen atom in one molecule and an electronegative atom (often oxygen or nitrogen) in another, important in the structure of water and DNA.