Microbiology

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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


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