Twin Studies of Certain Personality Traits Show a Heritability of ________

question 53

Multiple Choice

Twin studies of certain personality traits show a heritability of ________.

• A) 10 to 20 percent
• B) 40 to 50 percent
• C) 20 to 25 percent
• D) 80 to 90 percent

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Definitions:

Internal Intercostals

Muscles located between the ribs that help with breathing by reducing the space in the chest during exhalation.

External Intercostals

Muscles located between the ribs that help expand the thoracic cavity during inspiration.

Scalene

Refers to a group of three paired muscles in the lateral neck that facilitate breathing and are involved in various neck movements.

Closes the Anal Opening

This term likely refers to the sphincter ani externus muscle, which controls the opening and closing of the anus.