Which bacterial species normally provides a beneficial or protective role to the human host_______________?
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Answer: A. Streptococcus sanguis
Explanation
Streptococcus sanguis is a normal commensal bacterium that helps maintain oral health. It colonizes dental surfaces and inhibits the proliferation of harmful pathogenic bacterial species. Beneficial commensals contribute to the stability of the protective oral microbial ecosystem. The human oral cavity hosts a complex community of diverse microorganisms living in balance. Commensal organisms protect host tissues by occupying ecological niches and producing inhibitory substances. Disruption of the oral microbiome can lead to opportunistic infections or dental diseases.
Probiotic research explores utilizing beneficial oral streptococci to prevent dental caries and periodontal disease. Maintaining a healthy balance of oral flora is essential for overall systemic and dental well-being. Dental prophylaxis aims to preserve beneficial flora while controlling pathogenic plaque accumulation. Porphyromonas gingivalis is a major periodontal pathogen linked to chronic gum tissue destruction. Treponema denticola is a spirochete associated with severe forms of periodontal disease. Spirochetes in the oral cavity frequently contribute to pathological conditions rather than protection.
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