In the Equation Σ % = 100

question 2

Multiple Choice

In the equation Σ % = 100.0, the symbol Σ signifies:

• A) A percentage
• B) The sum of
• C) A data value
• D) A frequency

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Definitions:

Backflow

The flow of a fluid in a direction opposite to its usual or intended direction, often causing contamination or malfunction in plumbing or in bodily systems.

Valves

Structures present in the heart and veins that maintain unidirectional flow of blood by opening and closing in response to pressure differences.

Venous Valves

Structures within veins that prevent the backward flow of blood, crucial for blood returning to the heart.

Tunica Media

The middle layer of the wall of a blood vessel consisting mainly of smooth muscle cells and elastic fibers, responsible for regulating the diameter of the vessel.