A Scientist Is Trying to Test a Theory About the Relationship

question 285

Multiple Choice

A scientist is trying to test a theory about the relationship between people's consumption of alcohol and their longevity. Which of the following variables would the scientist NOT hold constant?

• A) the past histories of heart and lung disease
• B) the amount of dietary fat that people in the experimental group consumed
• C) the amount of alcohol that people in the experimental group consumed
• D) the amount of cigarettes that people in the experimental group smoked

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Definitions:

Capillary Networks

A complex, interconnected web of capillaries that facilitates efficient exchange of oxygen, nutrients, and waste products between blood and tissues.

Laplace's Law

A principle that describes the relationship between the pressure, volume, and tension of spherical and cylindrical shapes, often applied in cardiovascular and respiratory physiology.

Pressure Differences

Variations in pressure between two areas, which can result in fluid or air movement from the higher pressure area to the lower pressure area.

Endothelium

The single layer of cells lining the blood and lymphatic vessels, heart, and other cavities in the body, instrumental in vascular function.