Question 1

Which of the following best describes the role of microbes in the nitrogen cycle?

Accepted Answer

Microbes convert nitrogen gas ($$N_2) $$from the air into organic compounds usable by plants.

Question 2

Which statement correctly differentiates normal microbiota from transient microbiota?

Accepted Answer

Normal microbiota are acquired before birth and may colonize the body indefinitely, while transient microbiota colonize the body fleetingly.

Question 3

Which of the following is NOT a characteristic of bacteria?

Accepted Answer

They have chitin cell walls.

Question 4

Pasteur’s experiment disproved spontaneous generation by showing that:

Accepted Answer

Microorganisms did not appear in the broth unless exposed to air containing microbes.

Question 5

Which equation best represents the microbial conversion of sugar to alcohol during fermentation?

Accepted Answer

$$C_6H_{12}O_6$ \rightarrow 2C_2H_5OH + 2CO_2$$

Question 6

Which of the following is a major contribution of Robert Koch to microbiology?

Accepted Answer

He developed experimental steps (Koch’s postulates) to demonstrate that a specific microbe causes a specific disease.

Question 7

Which of the following is a correct application of scientific nomenclature?

Accepted Answer

The genus is capitalized and the species is lowercase, both italicized, e.g., $$	extit{Escherichia coli}.$$

Question 8

Which of the following statements about viruses is TRUE?

Accepted Answer

Viruses are acellular and can only replicate inside a living host cell.

Question 9

Which of the following is a real-world example of bioremediation?

Accepted Answer

Bacteria degrading oil spills in marine environments.

Question 10

Which factor is NOT a contributor to the emergence of infectious diseases?

Accepted Answer

Increased use of pasteurization in food processing.

Question 11

Which of the following is a correct definition of resistance?

Accepted Answer

The ability of the body to ward off disease.

Question 12

Which of the following is a benefit of biofilms in aquatic ecosystems?

Accepted Answer

Biofilms provide food for aquatic organisms.

Question 13

Which group of microorganisms is characterized by cellulose cell walls and the ability to produce oxygen via photosynthesis?

Accepted Answer

Algae

Question 14

Which of the following is an example of biotechnology that uses recombinant DNA technology?

Accepted Answer

Bacteria engineered to produce human insulin.

Question 15

Which equation best represents the microbial degradation of organic matter in sewage treatment?

Accepted Answer

$$C_xH_yO_z + O_2$ ightarrow CO_2$ + H_2O + 	ext{other by-products}$$

Question 16

Which of the following is a plausible reason why bacteria in biofilms are often resistant to antibiotics?

Accepted Answer

The extracellular matrix of biofilms limits antibiotic penetration.

Question 17

Which of the following is a correct statement about the Human Microbiome Project?

Accepted Answer

It aimed to determine the makeup of typical microbiota in various areas of the human body.

Question 18

Which of the following is NOT a benefit provided by normal microbiota?

Accepted Answer

They cause infectious diseases.

Question 19

Which of the following is a correct definition of biogenesis?

Accepted Answer

Living cells arise only from preexisting living cells.

Question 20

Which of the following is a plausible scenario illustrating the application of Koch’s postulates?

Accepted Answer

A scientist isolates a bacterium from a diseased animal, grows it in pure culture, and demonstrates that it causes the same disease when introduced into a healthy animal.

Chapter 1: The Microbial World and You – Study Notes

Guida di studio - Domande di pratica

Study guide - Flashcard