Question

Invading microorganisms sometimes enter the body and threaten its health. How does the body protect itself from these invaders?
A.
The immune system collects and stores the invading organisms.
B.
The respiratory system removes invaders from the blood.
C.
The immune system kills or disables the invading organisms.
D.
The respiratory system surrounds the invaders with carbon dioxide.

Answer 1

C.

The immune system detects invading microorganisms and kills or disables them. Innate defenses (barriers, phagocytes, inflammation) act quickly and the adaptive immune response (B and T lymphocytes, antibodies, memory cells) specifically neutralizes and removes pathogens.