Biofilms are NOT _________.

• A. They are highly susceptible to the body's defense mechanisms.
• B. They are NOT highly susceptible to the body's defense mechanisms.
• C. They are easily destroyed by disinfectants.
• D. They are only found in water lines.

Answer: (B)

Biofilms are resilient communities of microorganisms encased in a protective matrix that forms on surfaces. This structure makes them not easily attacked by the body's defenses. Immune cells and antibodies have trouble penetrating the matrix, and cells inside biofilms often grow slowly, which reduces their susceptibility to immune killing and to many antibiotics. As a result, they persist despite immune responses. Disinfectants also struggle to fully eradicate biofilms once they’re established, because the matrix blocks penetration and creates microhabitats with varying conditions. And biofilms aren’t limited to water lines—they can form on skin, medical devices, pipes, and other surfaces. That’s why the statement that they are not highly susceptible to the body's defense mechanisms is the best descriptor.