$$\mathrm{C_6H_{12}O_6$} + 6\,O_2$ \rightarrow 6\,CO_2$ + 6\,H_2O + \text{energy (ATP)}$$

Question 1

Which of the following best describes a chemoautotroph?

Accepted Answer

An organism that uses inorganic compounds for energy and CO$$_2 as a $$carbon source.

Question 2

A bacterium is placed in a solution with a higher solute concentration than its cytoplasm. What will most likely happen to the cell?

Accepted Answer

The cell will lose water and shrink due to osmosis.

Question 3

Which of the following is a micronutrient required by bacterial cells?

Accepted Answer

Zinc (Zn)

Question 4

Which process is responsible for the movement of water across a selectively permeable membrane?

Accepted Answer

Osmosis

Question 5

A facultative anaerobe is best described as an organism that:

Accepted Answer

Can grow with or without oxygen, using aerobic respiration when oxygen is present.

Question 6

Which equation correctly represents aerobic respiration?

Accepted Answer

$$\mathrm{C_6H_{12}O_6$} + 6\,O_2$ ightarrow 6\,CO_2$ + 6\,H_2O + 	ext{energy (ATP)}$$

Question 7

Which adaptation allows halophilic bacteria to survive in high-salt environments?

Accepted Answer

They increase the salinity of their cytoplasm to match the environment.

Question 8

Which phase of the bacterial growth curve is characterized by rapid cell division and maximum metabolic activity?

Accepted Answer

Log (exponential) phase

Question 9

A bacterial culture is growing in a chemostat. What is the main advantage of this system?

Accepted Answer

It maintains the culture in a biochemically active state by providing a continuous supply of nutrients.

Question 10

Which of the following best describes a mutualistic relationship?

Accepted Answer

Both organisms benefit from the relationship.

Question 11

Which enzyme is responsible for converting superoxide radicals to hydrogen peroxide in bacteria?

Accepted Answer

Superoxide dismutase

Question 12

A bacterium that grows optimally at 15°C and cannot grow above 20°C is classified as a:

Accepted Answer

Psychrophile

Question 13

Which of the following is NOT a form of active transport?

Accepted Answer

Facilitated diffusion

Question 14

Which method allows for the direct microscopic count of bacteria in a sample?

Accepted Answer

Cytometer

Question 15

Which of the following best explains why concentrated salt solutions are used to preserve food?

Accepted Answer

Salt solutions create a hypertonic environment, causing microbial cells to lose water and inhibiting growth.

Question 16

Which of the following is a real-life example of synergism in microbiology?

Accepted Answer

Two different bacteria in dental plaque cooperate to form a biofilm, enhancing survival.

Question 17

Which of the following statements about biofilms is TRUE?

Accepted Answer

Biofilms involve quorum sensing, where cells communicate to coordinate activity.

Question 18

A bacterial population doubles every 30 minutes. If you start with 1 cell, how many cells will there be after 3 hours?

Accepted Answer

64

Question 19

Which of the following is an example of a growth factor for bacteria?

Accepted Answer

Essential amino acid

Question 20

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

Accepted Answer

The rate of cell division equals the rate of cell death.

Microbial Nutrition and Growth: A Comprehensive Study Guide

Study Guide - Practice Questions