Microbiology: Biofilms and Culture Media

These flashcards cover the key concepts of biofilms, culture media, and various types of media used in microbiology, helping to reinforce understanding for exam preparation.

What are biofilms?

Thin slimy layers of bacteria that congregate and grow on surfaces.

What is quorum sensing?

Cell-to-cell communication that allows bacteria to coordinate activities and function as a unit.

Why are biofilms a concern in healthcare?

About 70% of human infections involve biofilms, often leading to nosocomial infections.

What is culture media?

The substance used to grow bacteria in the lab, providing nutrients for their growth.

What is agar and its function in culture media?

A solidifying agent used to create a solid medium for growing bacteria, having no nutritional value.

What is the difference between chemically defined media and complex media?

Chemically defined media has a known exact composition, while complex media can vary from batch to batch.

What is selective media?

Media that contains ingredients that allow the growth of specific types of bacteria while inhibiting others.

What does differential media do?

Media that allows for the differentiation of organisms based on their characteristics, such as color change.

What is an enrichment agar?

A special type of agar used to recover organisms present in small numbers.

What is a facultative parasite?

An organism that can live outside a host for a period but prefers to replicate within a host.

What is an obligate parasite?

An organism that cannot grow on artificial media and must have a host to survive.

What is the role of phenol red in mannitol salt agar?

It serves as a pH indicator that shows whether fermentation occurs by changing color.