Which term describes disease-causing organisms?

• A. Pathogens
• B. Antibodies
• C. Enzymes
• D. Hormones

Answer: (A)

Disease-causing organisms are called pathogens. They include bacteria, viruses, fungi, and parasites that can invade the body, damage tissues, and lead to illness. The word helps separate harmful agents from harmless or beneficial microbes that normally live in and on us. Antibodies are the immune system’s proteins that recognize and neutralize pathogens, not the disease-causing agents themselves. Enzymes are biological catalysts that speed up chemical reactions, and hormones are signaling molecules that regulate body processes. While some microbes are harmless or beneficial, those that cause disease fit the definition of pathogens.