What is one benefit of normal flora?

What is one benefit of normal flora?

• A. They compete with potentially pathogenic bacteria for attachment sites and nutrients.
• B. They produce toxins that damage host tissues.
• C. They always cause disease in compromised hosts.
• D. They remove attachment sites needed by pathogens.

Answer: (A)

Normal flora protect us by creating colonization resistance: they occupy binding sites on mucosal surfaces and consume nutrients that potential pathogens would need. By filling these niches and depleting resources, they make it harder for invasive bacteria to attach and grow, reducing infection risk. While some microbes can produce toxins or cause disease in people with weakened defenses, that's not a general benefit of the normal flora. They don’t “remove” attachment sites; they outcompete pathogens for them. This is why competition for attachment sites and nutrients is the most accurate and protective benefit of the normal flora.

Normal flora protect us by creating colonization resistance: they occupy binding sites on mucosal surfaces and consume nutrients that potential pathogens would need. By filling these niches and depleting resources, they make it harder for invasive bacteria to attach and grow, reducing infection risk. While some microbes can produce toxins or cause disease in people with weakened defenses, that's not a general benefit of the normal flora. They don’t “remove” attachment sites; they outcompete pathogens for them. This is why competition for attachment sites and nutrients is the most accurate and protective benefit of the normal flora.