At the End of the Civil War, What Communications System

question 49

Multiple Choice

At the end of the Civil War, what communications system did the railroads use to coordinate their complex flow of rail cars?

• A) The telephone
• B) The Pony Express
• C) The magnetic telegraph
• D) The internet
• E) Text-messaging

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Definitions:

Sarcoplasmic Reticulum

A specialized type of endoplasmic reticulum found in muscle cells, involved in the regulation of calcium ions to facilitate muscle contraction.

Sarcomere Contraction

The process by which muscle fibers contract, shortening the sarcomere, the basic unit of muscle fiber, thereby generating force.

Glycerin

A simple polyol compound often used in pharmaceutical formulations, foods, and personal care products for its moisturizing and emollient properties.

Skeletal Muscle Fibers

Long, cylindrical cells that make up skeletal muscles, responsible for voluntary body movements.