The Human Body Is Constantly Challenged by Pathogens in the Environment

question 16

Multiple Choice

The human body is constantly challenged by pathogens in the environment. It is not infected by every pathogen it encounters because the microbial flora

• A) engulf the pathogenic bacteria.
• B) produce conditions at the microenvironmental level that block colonization.
• C) prime our immune system.
• D) activate and support the action of antigen-presenting cells, cytokines, and cell-mediated immunity.

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Definitions:

Neurons

Specialized cells that convey nerve signals, serving as the fundamental components of the nervous system.

Nerves

Bundles of axons coated in myelin that travel together through the body.

Cerebellum

A region of the brain located at the back of the skull, playing key roles in motor control, coordination, and balance.

Reticular Activating System

A network of neurons located in the brainstem that plays a critical role in controlling arousal and alertness.