Question 1

Which of the following statements best describes a microbe?

Accepted Answer

A microscopic organism that cannot be seen with an unaided eye and typically consists of a single cell.

Question 2

Which scientist is credited with disproving the theory of spontaneous generation using the swan-neck flask experiment?

Accepted Answer

Louis Pasteur

Question 3

Koch’s postulates are used to:

Accepted Answer

Establish a causative link between a specific microbe and a disease.

Question 4

Which of the following is NOT a domain of life according to the three-domain system?

Accepted Answer

Fungi

Question 5

Which of the following best explains why viruses are not classified as prokaryotes or eukaryotes?

Accepted Answer

Viruses lack cellular structure and are acellular entities.

Question 6

Which scientist first observed single-celled microbes using a single-lens microscope and called them 'small animals'?

Accepted Answer

Antonie van Leeuwenhoek

Question 7

Which of the following is a correct statement about the human microbiome?

Accepted Answer

The human body contains approximately as many microbes as human cells.

Question 8

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

Accepted Answer

Mitochondria in eukaryotic cells deriving from ancient bacteria.

Question 9

Which scientist developed the first vaccines using weakened strains of microbes?

Accepted Answer

Louis Pasteur

Question 10

Which of the following best describes the role of lithotrophs in the environment?

Accepted Answer

They feed solely on organic minerals and contribute to nutrient cycling.

Question 11

Which equation best represents the relationship between the number of microbial cells and human cells in the human body?

Accepted Answer

$N_{microbes} \approx N_{human\ cells}$

Question 12

Which of the following is a key contribution of Florence Nightingale to medical microbiology?

Accepted Answer

She pioneered the use of medical statistics to demonstrate the impact of disease in warfare.

Question 13

Which scientist is credited with the discovery of antibiotics, specifically penicillin?

Accepted Answer

Alexander Fleming

Question 14

Which of the following is a correct sequence of events in the development of medical microbiology?

Accepted Answer

Observation of microbes → Disproving spontaneous generation → Koch’s postulates → Vaccination → Discovery of antibiotics

Question 15

Which of the following best explains the importance of agar in microbiology?

Accepted Answer

Agar is a gelling agent derived from red algae that solidifies liquid culture medium, allowing for the growth of pure bacterial colonies.

Question 16

Which of the following is a plausible reason why Koch’s postulates may not always be applicable to all infectious diseases?

Accepted Answer

Some pathogens cannot be grown in pure culture outside the host.

Question 17

Which scientist’s work led to the recognition of Archaea as a distinct domain of life?

Accepted Answer

Carl Woese

Question 18

Which of the following best describes the process of genome sequencing in microbiology?

Accepted Answer

Determining the order of nucleotides in a microbe’s chromosomal DNA.

Question 19

Which equation represents the size range of microbes?

Accepted Answer

$0.2\ \mu m \leq size \leq 5\ mm$

Question 20

Which of the following is a real-world application of enrichment cultures developed by Winogradsky?

Accepted Answer

Selective growth of microbes that can metabolize specific nutrients from environmental samples.

Microbial Life: Origin and Discovery – Chapter 1 Study Notes

Study Guide - Practice Questions