Which term describes an organism that can cause disease?

• A. Pathogenic
• B. Nonpathogenic
• C. Benign
• D. Harmless

Answer: (A)

Pathogenic describes an organism that has the ability to cause disease in a host. In other words, it’s capable of leading to illness or disease when it invades or colonizes tissue. This is the precise term for organisms that can cause disease, such as certain fungi, bacteria, or other pathogens that affect turf. The other terms describe organisms that do not cause disease or are considered harmless, so they don’t fit the idea of an organism that can cause disease. Some organisms may be opportunistic pathogens, causing disease under stress or with weakened defenses, but their defining characteristic is the potential to cause disease, which is what pathogenic captures.