MCB 101 FINAL EXAM QUESTIONS WITH VERIFIED
ANSWERS
Given the following growth curve which letter correctly represents the different phases -
Answers - C: Stationary
B: Death
D: Exponential
A: Lag
Based on prior experiments, you have determined that for a culture of S. aureus an
absorbance reading of 1.0 AU650 is approximately equal to 4.5 x 10^6 cells/mL.
How many cells should be present after 6 generations in a 1 mL culture, if the initial cell
culture had an absorbance reading of 0.5? - Answers - 14000000
"AU" is an abbreviation for a species of bacteria, Aerogenes uflatulans - Answers -
False
In the graph shown immediately above, both of the growth curves pertain to Vibrio
natriegens. - Answers - True
"AU-25C" refers to the growth of a strain of E. coli called AU-25C, at temperature of 37
degrees celsius - Answers - False
AU650 is directly related to the concentration of bacteria - Answers - True
The generation time for Vibrio netriegens is longer at 45 degrees celsius than it is at 37
degrees celsius - Answers - True
Vibrio natriegens grows faster than Escherichia coli - Answers - False
The optimal growth temperature for Vibrio natriegens is 37 degrees celsius - Answers -
False
Vibrio natriegens reaches stationary phase faster at 37 degrees celsius than at 25
degrees celsius - Answers - True
If the temperature gets above the optimal growth temperature, the bacteria will be under
stress and may die - Answers - True
A lower temperature makes an enzyme-catalyzed chemical reaction go faster because
the product is more stable - Answers - False
, An increase in temperature, as long as it is at or below the optimal growth temperature,
helps bacteria to grow faster - Answers - True
For an enzyme-catalyzed chemical reaction, raising the temperature always makes the
reaction go faster - Answers - False
Given the above graph and data table, calculate the value of the growth rate constant, k
for E. coli in hr-1 - Answers - 2.3990
Using the same data, calculate the value of the generation time, g for E. coli in hrs. -
Answers - 0.4168
Approximately how many generations occurred during exponential growth for E. coli? -
Answers - 3.9983
In which case would the shortest lag period most likely occur? - Answers - Transfer from
old complex medium to fresh complex medium
How does incubating the culture with shaking influence growth of the bacteria? -
Answers - Shaking improves overall aeration, increasing oxygen content in the media
The colorful bacteria that live in hot springs - Answers - Thermophile
Optimal growth at ~10 degrees celsius - Answers - Psychrophile
Optimal growth at ~65 degrees celsius - Answers - Thermophile
That weird smelling bacteria growing in your refrigerator - Answers - Psychrophile
Optimal growth at ~35 degrees celsius - Answers - Mesophile
Optimal pH is ~7 - Answers - Neutrophile
The bacteria found in the soda lakes of western states - Answers - Alkaliphile
Optimal pH is ~3.5 - Answers - Acidophile
Bacteria that live in Greek yogurt - Answers - Acidophile
Grow solely by fermentation but are able to tolerate oxygen - Answers - Faculatative
Anaerobe
Bacteria that only grow at the top of a broth culture tube - Answers - Obligate Aerobe
Bacteria that only grow at the bottom of a broth culture tube - Answers - Obligate
Anaerobe
ANSWERS
Given the following growth curve which letter correctly represents the different phases -
Answers - C: Stationary
B: Death
D: Exponential
A: Lag
Based on prior experiments, you have determined that for a culture of S. aureus an
absorbance reading of 1.0 AU650 is approximately equal to 4.5 x 10^6 cells/mL.
How many cells should be present after 6 generations in a 1 mL culture, if the initial cell
culture had an absorbance reading of 0.5? - Answers - 14000000
"AU" is an abbreviation for a species of bacteria, Aerogenes uflatulans - Answers -
False
In the graph shown immediately above, both of the growth curves pertain to Vibrio
natriegens. - Answers - True
"AU-25C" refers to the growth of a strain of E. coli called AU-25C, at temperature of 37
degrees celsius - Answers - False
AU650 is directly related to the concentration of bacteria - Answers - True
The generation time for Vibrio netriegens is longer at 45 degrees celsius than it is at 37
degrees celsius - Answers - True
Vibrio natriegens grows faster than Escherichia coli - Answers - False
The optimal growth temperature for Vibrio natriegens is 37 degrees celsius - Answers -
False
Vibrio natriegens reaches stationary phase faster at 37 degrees celsius than at 25
degrees celsius - Answers - True
If the temperature gets above the optimal growth temperature, the bacteria will be under
stress and may die - Answers - True
A lower temperature makes an enzyme-catalyzed chemical reaction go faster because
the product is more stable - Answers - False
, An increase in temperature, as long as it is at or below the optimal growth temperature,
helps bacteria to grow faster - Answers - True
For an enzyme-catalyzed chemical reaction, raising the temperature always makes the
reaction go faster - Answers - False
Given the above graph and data table, calculate the value of the growth rate constant, k
for E. coli in hr-1 - Answers - 2.3990
Using the same data, calculate the value of the generation time, g for E. coli in hrs. -
Answers - 0.4168
Approximately how many generations occurred during exponential growth for E. coli? -
Answers - 3.9983
In which case would the shortest lag period most likely occur? - Answers - Transfer from
old complex medium to fresh complex medium
How does incubating the culture with shaking influence growth of the bacteria? -
Answers - Shaking improves overall aeration, increasing oxygen content in the media
The colorful bacteria that live in hot springs - Answers - Thermophile
Optimal growth at ~10 degrees celsius - Answers - Psychrophile
Optimal growth at ~65 degrees celsius - Answers - Thermophile
That weird smelling bacteria growing in your refrigerator - Answers - Psychrophile
Optimal growth at ~35 degrees celsius - Answers - Mesophile
Optimal pH is ~7 - Answers - Neutrophile
The bacteria found in the soda lakes of western states - Answers - Alkaliphile
Optimal pH is ~3.5 - Answers - Acidophile
Bacteria that live in Greek yogurt - Answers - Acidophile
Grow solely by fermentation but are able to tolerate oxygen - Answers - Faculatative
Anaerobe
Bacteria that only grow at the top of a broth culture tube - Answers - Obligate Aerobe
Bacteria that only grow at the bottom of a broth culture tube - Answers - Obligate
Anaerobe
