When will the quorum sensing signaling molecule be in high concentration during biofilm development?

• A. During the attachment phase.
• B. During the quorum phase.
• C. When the bacterial population density is low.
• D. When the bacteria population density is high.

Answer: (D)

Verified step by step guidance

1. Understand the concept of quorum sensing: Quorum sensing is a mechanism by which bacteria communicate with each other using signaling molecules. This process allows bacteria to coordinate their behavior based on population density.
2. Identify the role of signaling molecules: In quorum sensing, signaling molecules are produced and released by bacteria. As the population density increases, the concentration of these molecules also increases.
3. Recognize the phases of biofilm development: Biofilm development typically includes phases such as attachment, microcolony formation, maturation, and dispersal. Quorum sensing is crucial during the maturation phase when the bacterial population is high.
4. Connect population density with signaling molecule concentration: When the bacterial population density is high, the concentration of quorum sensing signaling molecules reaches a threshold that triggers changes in gene expression, leading to coordinated behavior such as biofilm maturation.
5. Conclude the relationship: High bacterial population density results in high concentrations of signaling molecules, facilitating communication and coordination among bacteria during biofilm development.