Influenza Is Caused by a Virus

question 31

Multiple Choice

Influenza is caused by a virus. This virus is an example of a broad category of disease-causing organisms called __________.

• A)pathogens
• B)antibodies
• C)antigens
• D)leukocytes

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Definitions:

Hold-Off Chamber

The rear chamber in a spring brake assembly that compresses the park spring when charged with air. Consists of a chamber, diaphragm, and powerful coil spring.

Parking Brakes

A secondary braking system, usually mechanically operated, designed to hold a vehicle stationary when parked.

Trailer Lock

A security device or mechanism designed to prevent the unauthorized detachment or theft of a trailer by locking it to the towing vehicle or immobilizing its wheels.

Severe Braking

A situation where brakes are applied forcefully and suddenly, often in an emergency, to reduce vehicle speed quickly.