Many Cities in the American Southwest Rely on Sources of Drinking

question 1

Multiple Choice

Many cities in the American Southwest rely on sources of drinking water that contaminated with __________________.

• A) arsenic
• B) lead
• C) coliform bacteria
• D) DDT
• E) none of these are correct.

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Definitions:

Dendritic Cells

Immune cells that process antigen material and present it on their surface to T-cells, initiating an adaptive immune response.

CD4

A glycoprotein found on the surface of immune cells like T helper cells, playing a key role in the immune system by aiding in the response to antigens.

Antibody Units

Individual molecules of antibodies, which are proteins produced by the immune system to identify and neutralize pathogens like bacteria and viruses.

Initial Injection

The first dose or administration of a substance or drug into a body or system.