Stonehenge Is an Ancient Observatory Built in

question 21

Multiple Choice

Stonehenge is an ancient observatory built in

• A)ancient Babylon.
• B)England.
• C)the Euphrates river valley.
• D)Greece.

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Definitions:

Antibodies

Proteins produced by the immune system in response to antigens, which they neutralize or mark for destruction by other immune cells.

B Cells

A type of white blood cell that plays a significant role in the immune system, particularly in the production of antibodies.

Complement

Set of proteins that circulate in inactive form in the blood; activated complement attracts phagocytes, coats antigenic particles, and punctures cells.

Immune Responses

The body's defensive mechanisms activated by the immune system to recognize and eliminate foreign substances or pathogens.