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Bacteria and Dental Plaque

APBIO-T3TNJV

Streptococcus mutans is a species of bacteria that colonizes the human mouth leading to production and secretion of a type of exopolysaccharide into the environment.

In large enough concentrations, exopolysaccharides form biofilms commonly referred to as dental plaque. This biofilm can protect the S. mutans bacteria beneath.

However, exopolysaccharide production by a single bacterium uses a lot of energy and resources and is a slow process.

Based on this information, which of the following conclusions is MOST logical?

A

S. mutans constantly produce and secrete exopolysaccharides into their environment.

B

S. mutans produce and secrete exopolysaccharides into their environment only when a person eats a diet rich in carbohydrates.

C

S. mutans produce and secrete exopolysaccharides only when the total population reaches high levels.

D

The abrasive action of tooth brushing stimulates S. mutans to produce and secrete exopolysaccharides.