Deck 1: Microbial Life: Origin and Discovery

Question 1

Which one of the following statements regarding microbial cells is FALSE?

A) Microbial cells acquire food, gain energy to build themselves, and respond to environmental change.
B) Most single-celled organisms require a microscope to render them visible, but some bacterial cells are large enough to be seen with naked eyes.
C) Microbes function as individual entities.
D) Many microbes form complex multicellular assemblages.
E) Viruses are not considered microbial cells.

Answer 1

C

Question 2

The discovery of microbes occurred in the ________ century?

A) seventeenth
B) eighteenth
C) nineteenth
D) twentieth
E) twenty-first

Answer 2

C

Question 3

What is the standard sterilization method for the controlled study of microbes?

A) boiling
B) pasteurization
C) filter sterilization
D) autoclaving
E) irradiation

Answer 3

D

Question 4

Semmelweis and Lister noted that many of their patients' deaths were due to

A) fungi.
B) Escherichia coli.
C) chlorine.
D) pathogen transmission by doctors.
E) Staphylococcus.

Question 5

Tyndall's spontaneous generation experiments occasionally failed due to

A) nutrient chirality.
B) dust.
C) fermentation.
D) lack of oxygen.
E) endospores.

Question 6

Who developed the concept of medical statistics?

A) Francis Crick
B) Florence Nightingale
C) Edward Jenner
D) Louis Pasteur
E) Alexander Fleming

Question 7

Analysis of DNA sequences reveals

A) the ancient convergence of two cell types (i.e., prokaryotes and eukaryotes).
B) that prokaryotes and eukaryotes evolved from a common ancestral cell.
C) that bacteria share a common ancestor with archaea but not with eukarya.
D) that prokaryotes are cells with a nucleus.
E) that the genome of Haemophilus influenzae has about 2 billion base pairs.

Question 8

Which of the following statements is FALSE?

A) A genome is the total genetic information contained in an organism's chromosomal DNA.
B) If a microbe's genome includes genes for nitrogenase, that microbe probably can fix nitrogen.
C) By comparing DNA sequences of different organisms, we can figure out how closely related they are.
D) Fred Sanger developed the first applicable DNA sequencing method.
E) Fred Sanger completed the sequences of Haemophilus influenzae.

Question 9

The environment of early Earth may have contained all of the following EXCEPT

A) ferrous iron.
B) methane.
C) ammonia.
D) oxygen.
E) hydrogen gas.

Question 10

The development of the theory of the "RNA world" resulted from the discovery of

A) archaea.
B) prions.
C) bacteria.
D) ribozymes.
E) endosymbionts.

Question 11

What did van Leeuwenhoek discover using microscopic observations before and after drinking hot beverages?

A) Heat did not kill microbes.
B) Heat killed microbes.
C) Heat did not kill algae.
D) Caffeine in coffee killed microbes.
E) The existence of spiral-shaped microbes.

Question 12

How did European invaders to North America kill much of the native population?

A) tuberculosis
B) leprosy
C) smallpox
D) HIV
E) bubonic plague

Question 13

A microbe is commonly defined as a ________ that requires a microscope to be seen.

A) virus
B) bacterium
C) single-cellular prokaryote
D) multicellular eukaryote
E) living organism

Question 14

Robert Koch won the Nobel Prize for his contribution to medical bacteriology regarding

A) Escherichia coli.
B) Bacillus subtilis.
C) Mycobacterium tuberculosis.
D) rabies.
E) smallpox.

Question 15

Which of these groups are considered to be microbes but NOT considered to be cells?

A) viruses
B) bacteria
C) archaea
D) protists
E) filamentous fungi

Question 16

The first person to visualize individual microbial cells was

A) Antonie van Leeuwenhoek.
B) Robert Hooke.
C) Louis Pasteur.
D) Lady Montagu.
E) Edward Jenner.

Question 17

What is the evidence that living cells existed on Earth up to 3.8 billion years ago?

A) microfossils
B) 16S ribosomal RNA
C) Miller and Urey's experiments
D) Martian folded rock formations
E) diatom shells

Question 18

The first cellular genomes to be sequenced were those of

A) humans.
B) bacteria.
C) viruses.
D) prions.
E) fungi.

Question 19

Florence Nightingale

A) is best known as the founder of professional nursing.
B) was the first to use disinfectant to demonstrate the significance of aseptic technique.
C) developed the pie chart of mortality data during the Crimean War.
D) performed the first controlled experiment on the chemical conversion of matter, known today as chemotherapy.
E) argued that the environment of early Earth contained mainly reduced compounds.

Question 20

Viruses are

A) infectious agents that infect exclusively multicellular organisms.
B) noncellular particles that take over the metabolism of a cell to generate more virus particles.
C) pathogens that replicate in complex growth media.
D) cellular particles that belong to the archaea domain.
E) microbes that consist of lipid membrane-enclosed genomes.

Question 21

Organisms that live symbiotically inside a larger organism are known as

A) organelles.
B) cyanobacteria.
C) mitochondria.
D) endosymbionts.
E) chloroplasts.

Question 22

Which of the following statements regarding viruses is FALSE?

A) Most are too small to be seen by a light microscope.
B) They are "filterable agents" that can pass through porcelain filters that have a pore size that blocks microbes.
C) Their genomes could be composed of DNA or RNA.
D) They are smaller than plasmids and prions.
E) Viral particles, when pure enough, can be crystallized.

Question 23

What was the basis for the original smallpox vaccine?

A) chickenpox virus
B) cowpox virus
C) rabies virus
D) smallpox virus
E) anthrax

Question 24

It took the advent of the polymerase chain reaction to detect the presence of the causative agent for which disease?

A) anthrax
B) tuberculosis
C) AIDS
D) rabies
E) smallpox

Question 25

All of the following are true about penicillin EXCEPT that it

A) was discovered by Alexander Fleming.
B) was an accidental discovery.
C) is produced by a bacterium.
D) was the first antibiotic used by humans.
E) was purified by Florey and Chain.

Question 26

How does the Winogradsky column differ from Koch's plate media?

A) Koch's media creates a gradient from oxygen-rich conditions at the surface to highly reduced conditions below.
B) The Winogradsky column is used for culturing viruses.
C) The Winogradsky column is used for growing extremophiles.
D) The Winogradsky column uses the kinds of nutrients that feed humans.
E) The bacteria that Winogradsky isolated can grow only on inorganic minerals.

Question 27

The word "vaccination" is derived from the Latin word vacca, which means

A) inject.
B) smallpox.
C) immunize.
D) cow.
E) pustule.

Question 28

You have isolated a bacterium that you believe to be the causative agent of a new disease in frogs. How would you test the third of Koch's postulates?

A) Determine the shape of the bacterial cells.
B) Inject the bacteria into a healthy frog.
C) Isolate the bacterium from a sick frog.
D) Show that the bacterium is not present in healthy frogs.
E) Grow a pure culture of the bacterium outside the frog.

Question 29

The gene expression machinery of archaea is MOST similar to

A) monera.
B) prokaryotes.
C) bacteria.
D) eukaryotes.
E) mitochondria.

Question 30

In the three-domain model, the bacterial ancestor of mitochondria derives from ancient

A) fungi.
B) cyanobacteria.
C) respiring bacteria.
D) archaea.
E) protists.

Question 31

Which of the following is NOT considered to be an extremophilic condition for bacteria?

A) high alkalinity
B) high salinity
C) high acidity
D) high nutrients
E) high temperature

Question 32

Suppose Pasteur's swan-necked flasks containing boiled broth became cloudy twenty-four hours after boiling. Which choice could best explain the turbidity or cloudiness in the broth without supporting spontaneous generation?

A) Endospores in the broth survived boiling and grew after the broth cooled.
B) Contaminating organisms in the broth killed by boiling became alive again after the broth cooled.
C) Chemicals in the broth came together to form living organisms.
D) The broth allowed light to pass through it with less interference after boiling.
E) Solid material in the broth dissolved during boiling.

Question 33

Carl Woese's discovery replaced the classification scheme of five kingdoms with a scheme of three

A) phyla.
B) domains.
C) classes.
D) orders.
E) genera.

Question 34

How do many animal endosymbionts grow?

A) on the surface of the host
B) on low nutrients
C) by reducing iron oxide
D) on inorganic minerals
E) in biofilms

Question 35

How did Sergei Winogradsky grow lithotrophs?

A) enrichment culture
B) organic media
C) pure culture
D) endosymbiosis
E) chain of infection

Question 36

The use of agar as a more robust gelling agent in solid media was suggested by

A) Robert Koch.
B) Ignaz Semmelweis.
C) Angelina Hesse.
D) Louis Pasteur.
E) Richard Petri.

Question 37

Which of the following organelles are thought to be of prokaryotic origin?

A) chloroplast
B) mitochondria
C) nucleus
D) chloroplast and mitochondria
E) chloroplast and nucleus

Question 38

Animal microbiomes are NOT significant in

A) digesting plant fibers.
B) bioluminescence.
C) protection from pathogens.
D) converting ammonia to nitrate.
E) providing nutrients to the host.

Question 39

In the three-domain model, the bacterial ancestor of chloroplasts derives from ancient

A) fungi.
B) cyanobacteria.
C) proteobacteria.
D) archaea.
E) protists.

Question 40

Penicillin was first used to save the lives of many people during which war?

A) the U.S. Civil War
B) the Korean War
C) the Vietnam War
D) World War I
E) World War II

Question 41

Taq polymerase forms the basis of a technique for

A) comparative genomics.
B) recombinant DNA.
C) X-ray diffraction.
D) DNA amplification.
E) protein synthesis.

Question 42

This scientist first discovered the process of transformation.

A) Francis Crick
B) Robert Koch
C) Edward Jenner
D) Louis Pasteur
E) Frederick Griffith

Question 43

What was the major complaint about Lazzaro Spallanzani's experiment to disprove spontaneous generation, and how did Louis Pasteur's swan-neck flasks overcome this?

Question 44

Describe the discoveries of Louis Pasteur while working with the French beer and wine manufacturers in assessing alcohol versus vinegar production during fermentation.

Question 45

Antonie van Leeuwenhoek worked as a cloth draper, inspecting the quality of cloth. How did this lead to his interest in microscopy?

Question 46

Define "attenuation" and describe some mechanisms used to attenuate pathogens.

Question 47

What is the MOST recent evidence suggesting that all life on Earth shares a common ancestry?

Question 48

The ultracentrifuge is a high-speed centrifuge ideally suited for separating individual

A) cellular proteins and nucleotides.
B) microbial cells.
C) mold spores.
D) secondary metabolites.
E) base pairs.

Question 49

Electron microscopes use what to focus the beam of electrons?

A) electromagnets
B) a condenser lens
C) light rays
D) X-ray diffraction
E) glass

Question 50

The study of and cause of disease in humans, animals, and plants is called

A) microbiology.
B) phylogeny.
C) genomics.
D) epidemiology.
E) forensics.

Question 51

The X-ray diffraction studies by which of the following scientists concluded that DNA was a double helix?

A) James Watson
B) Rosalind Franklin
C) Francis Crick
D) Maurice Wilkins
E) Kary Mullis

Question 52

How do microbes help in the extraction of minerals?

Question 53

Describe the effects of three microbial diseases that have significantly affected human populations throughout history.

Question 54

Why did it take so long for humans to determine that microbes cause infectious diseases?

Question 55

In 1975, scientists held a conference at Asilomar to regulate and restrict the field of

A) recombinant DNA.
B) comparative genomics.
C) DNA sequencing.
D) DNA amplification.
E) forensic microbiology.

Question 56

Robert Koch's postulates have not been used to prove HIV as the causative agent of AIDS. Why not?

Question 57

How are prokaryotes and eukaryotes different?

Question 58

What feature of bacteria facilitated the DNA revolution in the 1970s?

A) They are very small.
B) They readily recombine DNA.
C) They have very large genomes.
D) All of their genes were known.
E) They do not cause disease.

Question 59

Peter Mitchell and Jennifer Moyle discovered the ________ theory in the 1960s.

A) germplasm
B) evolution
C) chemiosmotic
D) DNA synthesis
E) polymerase chain reaction

Question 60

Which commonly used microbial classification advancement led to the tree by Carl Woese in 1977?

A) comparative genomics
B) microscopy
C) X-ray diffraction
D) protein sequencing
E) 16S rRNA sequencing

Question 61

How would you use Robert Koch's postulates to prove that a specific organism causes a new disease in mice?

Question 62

What is the significance of the work of Ignaz Semmelweis and Joseph Lister?

Question 63

What were Rosalind Franklin's contributions toward discovering the structure of DNA, and why wasn't she one of the recipients of the Nobel Prize for this discovery?

Question 64

If you want to produce DNA polymerases like those used in polymerase chain reaction (PCR) for amplification of DNA, from which natural environment would you try to isolate the producers?

Question 65

Briefly explain the endosymbiosis theory and the evidence that supports it.

Question 66

Is it true that only culturable bacteria contribute to ecology? Explain your answer.

Question 67

Explain why the organisms that were studied by Sergei Winogradsky could not be grown on Robert Koch's plate media containing agar or gelatin.

Question 68

Give two reasons why microbes have been difficult to classify.

Question 69

Briefly describe how the ultracentrifuge is used to determine the sizes of cellular macromolecules.

Question 70

Define the term "endosymbiont" and give an example of an endosymbiotic relationship found in nature.