What Changes Would Be Expected in the Size of the Heart

question 29

Multiple Choice

What changes would be expected in the size of the heart chambers and heart mass of a marathon runner?

• A) Both would decrease
• B) The size of the heart chambers would remain normal but the heart mass would increase
• C) No change would occur
• D) Both would increase

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Definitions:

Confounding Variable

A variable that influences both the dependent variable and independent variable, causing a spurious association.

Dependent Variable

The variable in an experiment that is expected to change as a result of manipulations of the independent variable.

Positive Correlation

An association between increases in one variable and increases in another—or between decreases in one and in another.

Height And Weight

Physical measurements that indicate the vertical stature and mass of a body, often used in assessing health and development.