MB-Chapter 6

temperature ranges

-psychrophiles: cold-loving (-10)- 20 -psychotrophs: between 0- 20 or 30 -mesophiles: moderate-temperature 10-50 -thermophiles: heat-loving 40-70 -hyperthermophiles: 65-110 Celsius

If a single bacterium reproduced every 30 minutes, how many would there be in 2 hours?

16 bacteria

If 95 colonies grow on a 1:10,000 dilution plate, how many bacteria were in the original sample?

950,000

Given a shallow pan and a deep pot with the same volume, which would cool faster? Why?

Deep pot

Is a colony formed as a result of streaking a plate always derived from a single bacterium? Why or why not?

No, there are other organisms that could contaminate it-Ex: staph forms clumps, so how can you be sure that there aren't other strains in that clump

Why is the prevention of biofilms important in a healthcare environment?

The advantages are that these are resistant to phagocytosis and antibiotics.These are important in the healthcare environment because infections that create biofilms are generally chronic/deep infections (UTI's pneumonia)

How is microbial growth impeded when high concentrations of sugar or salt are used to preserve food?

When a layer of a high-salt or high-sugar substance is used to preserve food, the food is protected from microbial invasions.

How is budding different from binary fission?

b- a new organism is formed bf- cell just splits