Microbiology Lab Exercise 7

microbes that require oxygen to grow but at much lower levels than 20% are

microaerophile

Microbes that can only grow when oxygen is not present are

obligate anaerobe

Microbes that can only grow when oxygen is present are

obligate aerobe

Microbes that can grow in oxygen but do not require oxygen for energy metabolism are

aerotolerant anaerobe

Microbes that are flexible and can grow with or without oxygen are

facultative anaerobe

Which bacteria have optimal growth between -5ºC to 15º C?

psychrophile

Which bacteria have optimal growth between 45ºC to 75ºC?

thermophile

Which bacteria have optimal growth between 25ºC to 45ºC?

mesophile

Which bacteria have optimal growth above 75ºC?

hyperthemophile

A bacterium that grows at a pH of 10 is a

alkaliphile

A bacterium that grows at a pH of 4 is a

acidophile

A bacterium that grows at a pH of 7 is a

neutrophile

These microbes can grow in excessive sugar concentrations.

osmophile

These microbes require a high concentration of sodium chloride in order to grow.

obligate halophile

These microbes can grow in moderate concentration of sodium chloride.

halotolerant

A cell that has more solutes than the surrounding environment is

hypertonic

A cell that has fewer solutes than the surrounding environment is

hypotonic

Water flow (into / out of) a cell that is hypotonic.

out of

Water flow (into / out of) a cell that is hypertonic.

into

When the temperature increases past the optimal, the hydrogen bonding in the RNA breaks down and the proteins denature in this structure.

ribosome

When the temperature increases past the optimal, lipids can be destroyed affecting which structure?

cell membrane

Which temperature results in white colonies of Serratia?

37 degrees Celsius

When the temperature decreases past the optimal, lipids can freeze and fracture affecting which structure?

cell membrane

When the temperature decreases past the optimal, the activity of this molecule will slow down.

enzyme

When the temperature increases past the optimal, these denature.

enzyme

Which temperature results in pinkish/red colonies of Serratia?

25 degrees Celsius

Based on the absorbance readings, which temperature does Serratia marcescens grow best at?

37 degrees Celsius

Based on the absorbance readings, which temperature does Escherichia coli grow best at?

37 degrees Celsius

Based on the absorbance readings, which temperature does Geobacillus stearothermophilus grow best at?

55 degrees Celsius

Based on the absorbance readings, which temperature does Serratia marcescens grow the worst at?

55 degrees Celsius

Based on the absorbance readings, which temperature does Escherichia coli grow the worst at?

55 degrees Celsius

Based on the absorbance readings, which temperature does Geobacillus stearothermophilus grow the worst at?

37 degrees Celsius

Based on the absorbance readings, which pH does Escherichia coli grow best at?

7

Based on the absorbance readings, which pH does Staphylococcus epidermidis grow best at?

5

Based on the absorbance readings, which pH does Alcaligenes faecalis grow best at?

7

Based on the absorbance readings, which pH does Saccharomyces cerevisiae grow best at?

5

Based on the absorbance readings, which pH does Escherichia coli grow the worst at?

3

Based on the absorbance readings, which pH does Staphylococcus epidermidis grow the worst at?

3

Based on the absorbance readings, which pH does Alcaligenes faecalis grow the worst at?

3

Based on the absorbance readings, which pH does Saccharomyces cerevisiae grow worst at?

10