Microbiology
The __________ produced by the genes Clostridium have the ability to survive harsh environmental conditions that can commonly kill the vegetative bacterial cells
Endospores
In what ways are Archaea similar to bacteria?
Energy sources used, prokaryotic cell structure, method multiplication, shapes and sizes
The work of John Tyndall and Ferdinand Cohn
Explained why some spontaneous generation investigators got different results from those of Pasteur
True or false: Scientists now understand the true diversity of microbial life and have determined the relationship between the millions of prokaryotes
False
Aerobic chemolithotrophs obtain energy by oxidizing reduced inorganic chemicals, using ______ as terminal electron acceptor
Oxygen
Cells that do not have a membrane-bound nucleus are called
Prokaryotic cells
Members of which bacterial genus are used to make Swiss cheese
Propionibacterium
Propionibacterium species produce _________ acid as their major fermentation end product
Propionic
The characteristic flavor and holes of Swiss cheese are caused by the fermentation products ____________ and ______________ respectively
Propionic acid; CO2
Algae and Protozoa are also referred to as ______, a diverse group that falls within the domain Eukarya
Protists
A reason why environments that are routinely exposed to O2 can support anaerobic growth is that _________
O2 consuming organisms depletes the oxygen levels
Cyanobacteria are a group of _________ bacteria
photosynthetic
What is the only shared feature of all microbes?
small size
A diverse group of Gram-negative bacteria that obtain energy by oxidizing inorganic nitrogen compounds such as ammonia or nitrate are known as
Nitrifiers
Many Cyanobacteria can convert nitrogen gas to ammonia, which is a process called ________
Nitrogen fixation
Nitrogen fixing Cyanobacteria can incorporate both _________ and ________ into organic material, thus generating a form of these nutrients that can be used by other organisms
Nitrogen; carbon dioxide
Compared to the range of types of plants and animals, microbes as a group are
more diverse
The Golden Age of Microbiology was the time when
most pathogenic bacteria were identified
True or false: Cyanobacteria are morphologically diverse, ranging in shape from unicellular organisms to filamentous multicellular associations.
True
True or false: Methane has produced by methanogens can be collected and used for generating electricity
True
Which of the following are classified as acellular infectious agents?
Viroids, prions and viruses
Oxygenic phototrophs use ________ as a source of electrons for reducing power, generating O2
Water
What are the three biological domains
Bacteria, Archaea, Eukarya
Cyanobacteria as a group are capable of __________
Both photosynthesis and nitrogen fixation
Peptidoglycan is found in the
Cell walls of bacteria
An organism that harvests energy by oxidizing inorganic chemicals, but not organic chemicals, is a ________
Chemolithrotrophs
The earliest phototrophs probably belonged to a group of bacteria called the _________
Cyanobacteria
Membrane-bound organelles are only found in the cell type called
Eukaryotic cell
An anaerobic chemoorganotroph that uses glucose for energy and pyruvate as it's terminal electron acceptor is performing _______
Fermentation
As a group, pseudomonas species ___________
Have extremely diverse biochemical capabilities
Environments that would most likely support the growth of methanogens
Human digestive tract, sewage, swamp, and marine sediment
During photosynthesis, anoxygenic phototrophs use _________ as a source of electrons to make reducing power
Hydrogen Sulfide
When surfer is used as a terminal electron acceptor in the metabolism of an organic compound, the products are carbon dioxide and _________
Hydrogen sulfide
In a healthy individual, anaerobes can regularly be found on and in the _________
Intestinal tract, skin and oral cavity
Anoxygenic phototrophs typically live in which of the following environments?
Lakes, bogs, upper layers of mud
_______ is credited with disproving spontaneous generation using broth in swan-neck flasks
Louis Pasteur
All of the following are emerging infectious diseases except
smallpox
Unlike the term microorganism, the word microbe also includes
viruses
Chemoorganotrophs that perform __________ often use sulfur or sulfate as a terminal electron acceptor
Anaerobic respiration
Which was likely the earliest photosynthesizing organisms?
Anoxygenic phototrophs
Methanogens are a group of __________ that produce methane by oxidizing ____________
Archea; H2
Sulfur reducing bacteria have a positive impact on the environment because they ________
Are an essential component of the sulfur cycle
An atmosphere that lacks O2 is called
Anoxic or anaerobic
Nitrifiers can be described as bacteria that
Obtain energy by oxidizing inorganic nitrogen compounds such as ammonium or nitrite
Archaea, like bacteria, are single-celled _______ that divide via the process of ________ _________
Organisms; binary fission
Nitrifying bacteria _________. Thus, levels of this gas can quickly decrease in aquatic environments.
Oxidize nitrogen compounds using O2
Pseudomonas species are Gram-negative rods that, unlike members of the family Enterobacteriaceae, are
Oxidize positive nonfermenters
As a group, chemolithotrophs __________ to obtain energy
Oxidize reduced inorganic chemicals such as hydrogen gas
Most bacteria have rigid cell walls that contain a unique compound called
Peptidoglycan
Obligate aerobes obtain energy using ___________ exclusively; none of them can ferment
Respiration
The concept of living things arising from vital forces in non-living or decomposing material was known as which of the following
Spontaneous generation
In 1749, John Needham produced results that _______ spontaneous generation when he showed that broths that had been boiled and then sealed with a cork ________
Support; could still give rise to microorganisms
In algae, photosynthesis takes place in _____, which have chlorophyll, a green pigment
chloroplasts
Technically speaking, viruses are not microorganisms because they are not
composed of cells
What does the scientific name of an organism include?
genus and species
The property of endospores that led to confusion in the experiments on spontaneous generation is their
heat resistance
_______ are a large group of photosynthetic eukaryotes that includes the multicellular seaweeds and many single-celled forms
Algae
A reason why environments that are routinely exposed to O2 can support anaerobic growth is that __________
O2 consuming organisms depletes the oxygen levels
The principle that microorganisms cause certain diseases is called
The Germ Theory of Disease
In eukaryotes, the genetic material is contained within a membrane-bound structure called
The nucleus
Why are nitrifiers of concern regarding their environmental impact?
They convert ammonium fertilizer to nitrate, which is more easily leached from soils and they consume dissolved O2 from waterways contaminated with nitrogen-containing wastes
Which of the following describes how fungi gain energy?
They degrade organic materials
Why were Louis Pasteur's experiments with swan-necked flasks so important in helping disprove the theory of spontaneous generation?
They ended arguments that a "vital force" was necessary for spontaneous generation, while preventing contamination from microbes in the air
Chemoorganotrophs oxidize _________ compounds such as glucose to obtain energy
organic
Which group of bacteria is best described as a diverse group of photosynthetic Gram-negative bacteria that inhabit a wide range of environments?
Cyanobacteria
All living organisms are now classified into three different taxonomic units called
Domains
Tyndall and Cohn's experiments in the 1870s showed the presence of a heat resistant form of bacteria called
Endospore
A testable explanation for an observation is called
Hypothesis
If all prokaryotes were eliminated from the planet,
all animals would die