Which of the following regarding antimicrobial control agents is false?

• A. Some agents work by disrupting microbial cell membranes.
• B. They always kill all microorganisms present, including endospores.
• C. They can be used to sterilize medical equipment.
• D. The effectiveness of an agent can depend on the concentration used.

Answer: (B)

Verified step by step guidance

1. Step 1: Understand the definition of antimicrobial control agents. These are substances or methods used to kill or inhibit the growth of microorganisms, including bacteria, fungi, and viruses.
2. Step 2: Review the modes of action of antimicrobial agents. Many agents work by disrupting microbial cell membranes, interfering with cell wall synthesis, or inhibiting protein or nucleic acid synthesis.
3. Step 3: Consider the concept of sterilization versus disinfection. Sterilization means killing all forms of microbial life, including highly resistant structures like endospores, while disinfection may not eliminate all microorganisms or endospores.
4. Step 4: Analyze the statement 'They always kill all microorganisms present, including endospores.' This is generally false because many antimicrobial agents do not kill endospores, which are highly resistant.
5. Step 5: Recognize that the effectiveness of antimicrobial agents depends on factors such as concentration, exposure time, and the type of microorganism, and that some agents can be used to sterilize medical equipment if they are capable of killing all microbes including endospores.