Biological and Information Systems Review

Flashcards based on introductory questions regarding biological organisms, enzymatic importance, and human information problems.

what does sterile mean?

sterile is defined as free of all living organisms.

why is aseptic technique necessary for pure cultures?

aseptic technique prevents contamination of the culture, the researcher, and the environment.

what are problems that arise when enumerating unstained preparations in microscopic counts?

difficult to distinguish between live and dead cells; small cells can be overlooked; motile cells are hard to count.

why do cells enter stationary phase?

depletion of essential nutrients, accumulation of waste products, and limited space/ oxygen.

define generation time.

the time required for microbial population to double in number.

what are the stages of biofilm formation?

1. attachment 2. colonization 3. development 4. dispersal.

why is biofilm formation a major problem in medicine?

biofilm protect bacteria from antibiotics and immune system, often leading to chronic infection on medical devices.

how hyperthermophile differ from a psychrophile?

hyperthermophile grow in extreme heat ( above 80 C), while psychrophiles thrive in cold temps (below 15 C).

what is Taq polymerase and why is it important?

A heat-stable DNA polymerase from Thermus aquatic is; essential for PCR because it survives high- temperature denaturation step.

How does an obligate aerobe differ from a facultative aerobe?

Obligate aerobe REQUIRE oxygen; facultative aerobes grow BETTER with oxygen, but CAN survive WITHOUT it.

Sterilization of media vs. Pasteurization of dairy?

sterilization kills all microbes; pasteurization uses heat to reduce microbial load and kill pathogens without spoilage.

Polymerase

A key biological entity noted for being important.