How Do Veins Prevent Backflow of the Low-Pressure Blood They

question 61

Multiple Choice

How do veins prevent backflow of the low-pressure blood they carry? Select the TWO answers that apply.

• A) The muscular contractions of the skeletal muscles in which the veins are found provide movement.
• B) Valves located in the veins prevent backflow.
• C) Capillaries allow blood to move in both directions so that backflow can be controlled.
• D) All of the answers are correct.
• E) None of the answers are correct.

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Definitions:

Long-run Aggregate Supply

Long-run aggregate supply represents the total output of goods and services that an economy can produce when it is operating at full capacity, unaffected by the price level in the long term.

Resource Prices

The costs associated with procuring the natural, human, and capital resources needed for producing goods and services.

Natural Rate

The unemployment rate or level of activity achieved in an economy when it is at full employment, without accelerating inflation.

Unemployment

The situation in which individuals who are capable of working are actively seeking work but are unable to find employment.