How does the immune system work - practice quiz

The itch, redness, and swelling after a mosquito bite are best explained by:

• Antibody memory from a prior infection

• Local inflammatory mediators released by tissue cells

• A drop in body temperature

• Activation of bone marrow stem cells only

Cytokines primarily function to:

• Strengthen antibody–antigen bonds only

• Carry oxygen to inflamed tissues

• Serve as chemical messages coordinating immune cells

• Digest pathogens directly

Tags

NGSS.HS-LS1-3

Which event is MOST directly driven by cytokine signaling?

• DNA replication in pathogens

• Recruitment of leukocytes (WBC) to infection sites

• Antigen mutation

• Fever reduction

Which statement BEST describes leukocytes?

• They are red blood cells that carry antibodies.

• They are platelets that help clot blood.

• They are white blood cells that identify and remove threats.

• They are neurons that transmit immune signals.

A patient with low leukocyte (WBC) count is MOST at risk for:

• Excessive clotting

• Oxygen toxicity

• Frequent infections

• Increased bone density

An antigen is:

• Any molecule recognized as “self”

• A molecule that triggers an immune response

• A cytokine that reduces inflammation

• An enzyme that digests pathogens

Antibodies help primarily by:

• Increasing pathogen mutation rate

• Neutralizing and tagging pathogens for destruction

• Lowering body temperature

• Converting antigens into cytokines

Which pairing is CORRECT?

• Phagocytes—make antibodies

• Lymphocytes—engulf pathogens

• Phagocytes—“engulf and digest” pathogens

• Lymphocytes—platelet producers

Fever’s role: Fever can help fight infection because it:

• Always kills all pathogens directly

• Slows pathogen replication and boosts immune efficiency

• Prevents cytokine signaling

• Blocks antibody production

Tags

NGSS.HS-LS1-3

Autoimmune disease: Autoimmunity occurs when the immune system:

• Fails to recognize any antigens

• Attacks the body’s own tissues as if foreign

• Becomes unable to produce cytokines

• Only uses innate defenses