Final answer:
Biofilms are complex microbial communities that adhere to surfaces and are protected by a matrix mainly composed of polysaccharides. They offer advantages to the microbes within, such as resistance to desiccation and antimicrobials, but pose significant challenges in clinical settings due to their resilience against treatments.
Step-by-step explanation:
The structures described in the question are known as biofilms, which are complex communities of different types of microbes that firmly adhere to surfaces. Biofilms usually arise when microorganisms, such as bacteria, adhere to a surface, begin to secrete a slimy, protective matrix consisting mainly of polysaccharides, and multiply to form a colony. This slimy matrix, sometimes referred to as extracellular polymeric substance (EPS), allows for a strong attachment and provides various benefits to the microbes within, such as protection from desiccation, predation, and the effects of antibiotics and disinfectants. Within a biofilm, microorganisms can communicate and coordinate their activities, which increases the community's overall resilience and survival capabilities, particularly in adverse conditions or when under attack by antimicrobial agents. However, biofilms can also contribute to a range of problems in medical settings, as they can form on medical devices and are associated with stubborn infections that are challenging to treat due to their enhanced resistance.