Question

1. what is the main function of the immune system?

a. to patrol the blood for nutrients
b. to produce plasma
c. to transport oxygen around the body
d. to protect the body against pathogens

Explanation:

• Option A: Nutrient patrol is not the immune system's role (e.g., digestive/circulatory systems handle nutrients).
• Option B: Plasma production is by the liver and bone marrow, not the immune system.
• Option C: Oxygen transport is done by red blood cells in the circulatory system.
• Option D: The immune system’s main job is to defend the body from pathogens (like bacteria, viruses) through mechanisms like white blood cells, antibodies, etc.

Answer:

D. To protect the body against pathogens