Question 1

Which of the following best describes an organism that uses inorganic carbon as its sole carbon source and light as its energy source?

Accepted Answer

Photoautotroph

Question 2

A microbiologist is culturing a bacterium that requires oxygen at levels between 2% and 10%. Which term best describes this organism?

Accepted Answer

Microaerophile

Question 3

Which of the following is NOT a benefit to microbes living in a biofilm?

Accepted Answer

Faster mutation rates

Question 4

Which of the following best describes the purpose of the streak-plate technique?

Accepted Answer

To obtain isolated colonies of bacteria

Question 5

Which type of microorganism would you most likely find living near hot springs?

Accepted Answer

Thermophile

Question 6

Which of the following is NOT a direct method for measuring microbial growth?

Accepted Answer

Turbidity

Question 7

A bacterium divides by binary fission every 30 minutes. If you start with 2 cells, how many will there be after 2 hours?

Accepted Answer

32 cells

Question 8

Which of the following best describes the lag phase of a bacterial growth curve?

Accepted Answer

Cells are adjusting to new environment and not dividing rapidly

Question 9

Which instrument is used to create a continuous culture where media and air are replenished in the container?

Accepted Answer

Chemostat

Question 10

Which of the following statements about quorum sensing is TRUE?

Accepted Answer

It allows microbes to sense population density and coordinate gene expression

Question 11

Which of the following best describes a selective medium?

Accepted Answer

A medium that inhibits the growth of some organisms while allowing others to grow

Question 12

Which of the following is the best method for preserving a bacterial culture for 10 years or longer?

Accepted Answer

Lyophilization

Question 13

Which of the following is a physical requirement for microbial growth?

Accepted Answer

Osmotic pressure

Question 14

Which of the following best describes a halophile?

Accepted Answer

An organism that grows best in high salt concentrations

Question 15

Which of the following is the best method for storing bacterial cultures for short periods of time?

Accepted Answer

Refrigeration

Question 16

Which of the following is true about the stationary phase of a bacterial growth curve?

Accepted Answer

The rate of cell division equals the rate of cell death

Question 17

Which of the following best describes the use of MacConkey agar?

Accepted Answer

It is both selective for Gram-negative bacteria and differential based on lactose fermentation

Question 18

Which of the following is the best way to measure microbial growth if the population of microbes in a liquid is very small?

Accepted Answer

Membrane filtration

Question 19

Which of the following is a chemical requirement for microbial growth?

Accepted Answer

Phosphorus

Question 20

During which phase of microbial growth are cells actively synthesizing enzymes to utilize nutrients?

Accepted Answer

Lag phase

Chpt 6 Lecture Microbial Nutrition and Growth: Structured Study Notes

Study Guide - Practice Questions