Why Is the Change in Sound Made by a Passing

question 19

Multiple Choice

Why is the change in sound made by a passing train's whistle similar to the reason the pitch rises quickly in systole and drops quickly in early diastole when measuring arterial sounds?

• A) Both are explained by B-mode ultrasonography.
• B) Both involve the science of plethysmography.
• C) Both are explained by the Doppler effect.
• D) Both are explained by the science of atomic behavior in a strong magnetic field such as MRI.

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Definitions:

Lose Heat

The process by which an object or organism transfers heat to its surroundings, leading to a decrease in its own temperature.

Cattle Grazing

The practice of allowing livestock, specifically cattle, to feed on grass in open fields or pastures.

Grasslands

Biomes characterized by large open areas of grasses, with very few trees, that can be found in both temperate and tropical regions of the world.

Desert

A barren area of landscape where little precipitation occurs, resulting in harsh living conditions for most plants and animals.