Since the Implementation of the Clean Air Act This Pollutant

question 148

Multiple Choice

Since the implementation of the Clean Air Act this pollutant has had the greatest percent decrease

• A) nitrogen oxides.
• B) carbon monoxide.
• C) sulfates.
• D) lead.

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Definitions:

Cell-Mediated Immunity

An immune response that does not involve antibodies but rather involves the activation of phagocytes, antigen-specific cytotoxic T-lymphocytes, and the release of various cytokines in response to an antigen.

Neutrophils

A type of white blood cell that plays a key role in the immune system by defending the body against infection.

Macrophages

Immune cells that engulf and digest cellular debris, foreign substances, microbes, and cancer cells in a process called phagocytosis.

Innate Immunity

The first line of defense in the immune system, consisting of physical, chemical, and cellular defenses against pathogens that are present from birth.