Question

fill in the blank question

molecules released by members of the biofilm that accumulate as the population grows and stimulate gene expression in its members are called molecules.

Explanation:

Identify the signaling mechanism and molecules

The process described is quorum sensing, which is a system of stimulus and response correlated to population density. The specific signaling molecules released by bacteria to coordinate this gene expression are called autoinducers.

Determine the correct blank term

The sentence ends with "...are called [blank] molecules." Since "molecules" is already present outside the blank, the adjective or noun modifier describing these specific signaling molecules is "autoinducer".

Answer:

Molecules released by members of the biofilm that accumulate as the population grows and stimulate gene expression in its members are called <blank>autoinducer</blank> molecules.