Question

a pathogenic bacterium invades a human respiratory system and begins to reproduce. why might it take several days for the bacterial host to notice the symptoms of illness? in this scenario, biofilm formation was ultimately unsuccessful. the activity of bacterial endotoxins and exotoxins have effectively canceled each other out. like many other coordinated bacterial activities, pathogenic effects (such as coughing and sneezing) are mediated by quorum sensing. bacteria have adaptations to mask disease symptoms during the early stages of infection, allowing them to fool the immune system of their host. the symptoms of bacterial infections are ultimately associated with viral activity, which happens more slowly.

Explanation:

Pathogenic bacteria can use quorum sensing to coordinate their activities. Quorum sensing allows bacteria to communicate and act in a coordinated manner based on their population density. In this case, it may delay the appearance of symptoms as they can suppress the effects of endotoxins and exotoxins that would normally trigger symptoms until their population is large - enough.

Answer:

Like many other coordinated bacterial activities, pathogenic effects (such as coughing and sneezing) are mediated by quorum sensing.