Which of the following terms refers to a substance in the blood that tends to neutralize harmful matter?
Show answer & explanation
Correct answer: D
Explanation
An antitoxin is an antibody produced by the body that specifically neutralizes toxins (harmful matter produced by microorganisms or other sources) within the blood.
Antibodies are proteins that bind to pathogens to neutralize them generally, but "antitoxin" specifically refers to those neutralizing toxins.
Antigens are substances that trigger an immune response, not neutralize them.
Antioxidants are substances that inhibit oxidation and neutralize free radicals in cells, not toxins in the blood.