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BIOL 203 MICROBIOLOGY LCC FINAL EXAM (2 LATEST VERSIONS)
NEWEST 2026 ACTUAL EXAM WITH COMPLETE QUESTIONS AND
CORRECT DETAILED ANSWERS (100% VERIFIED ANSWERS)
|ALREADY GRADED A+| ||PROFESSOR VERIFIED||
What is a bacterial endospore? Explain how endospore-forming
bacteria could cause a scientist to believe in spontaneous
generation. - ANSWER-A bacterial endospore is an organism that
is able to survive in extreme conditions due to their tough
structure.
Endospore-forming bacteria could cause scientists to believe in
spontaneous generation because, they can survive in extreme
conditions that would normally kill bacteria. In spontaneous
generation, it is said that living things appear from vital forces
existing in nonliving or decomposing matter, but there could be
bacterial endospore living in that situation without the scientists
knowing.
Describe how organisms are placed in the Three Domain
(Woese-Fox) classification system vs how organisms are placed
in the Five Kingdom (Traditional Wittaker) classification system.
Which classification system is more useful to a microbiologist and
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why? - ANSWER-Organisms are placed in the Three Domain
classification system by using the three main branches,
"Bacteria," Archaea," and "Eukarya." They are placed in each
domain based on what kind of cell they are (eukaryotic and
prokaryotic). Although prokaryotic cells are both Domain Bacteria
and Domain Archaea, the members of the Domain Archaea are
very different from the ones in Domain Bacteria as they are able
to live in severe environments and are also able to produce
metabolic byproducts.
Organisms are placed in the Five Kingdom classification system
by using certain levels that the organisms need to pass in order to
go on to the next level. The bottom level is the domain and the
organism works its way up to the top level, which is species.
It is more useful for a microbiologist to use the Three Domain
classification system because it classifies organisms into smaller
classifications rather than being broad. The Five Kingdom
classification system is more observation based while the Three
Domain classification system is more DNA based.
,3|Page
Why must an electron microscope be used to see most viruses?
Why can't they be seen using a light microscope? - ANSWER-An
electron microscope must be used to see most viruses because
viruses are too small to be seen by the optical microscope. The
electron microscope has a magnification of 5,000X to 1,000,000X
and it does not use light.
Viruses can't be seen using a light microscope because light
microscopes do not have as much magnification as the electron
microscope and you will not be able to see the viruses.
What is the difference between a mixed culture and a pure culture
of microbes? - ANSWER-The difference between a mixed culture
and a pure culture of microbes is that a mixed culture are multiple
species growing in a container while a pure culture is one species
growing in a container.
Mannitol Salt Agar and MacConkey Agar are two examples of
media that is both selective and differential. In your own words
describe what selective and differential mean. - ANSWER-
Selective- Contains one or more agents that restrain growth of a
certain microbe(s) but urge the growth of another.
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Differential- Allows several types of microbes to grow and show
differences among themselves.
All bacteria make humans ill. - ANSWER-False
In the three domain classification system, all prokaryotic cells are
grouped into Monera. - ANSWER-False
Angelina Hesse suggested adding ______ as a thickener to broth
in order to make solid media. - ANSWER-Agar
Koch's postulates were used - ANSWER-to definitively link one
microorganism to one disease.
In this class of microorganisms, all members are prokaryotes. -
ANSWER-bacteria
The theory that states life can arise from nonliving things and
would explain an infection by stating that first the body would be
BIOL 203 MICROBIOLOGY LCC FINAL EXAM (2 LATEST VERSIONS)
NEWEST 2026 ACTUAL EXAM WITH COMPLETE QUESTIONS AND
CORRECT DETAILED ANSWERS (100% VERIFIED ANSWERS)
|ALREADY GRADED A+| ||PROFESSOR VERIFIED||
What is a bacterial endospore? Explain how endospore-forming
bacteria could cause a scientist to believe in spontaneous
generation. - ANSWER-A bacterial endospore is an organism that
is able to survive in extreme conditions due to their tough
structure.
Endospore-forming bacteria could cause scientists to believe in
spontaneous generation because, they can survive in extreme
conditions that would normally kill bacteria. In spontaneous
generation, it is said that living things appear from vital forces
existing in nonliving or decomposing matter, but there could be
bacterial endospore living in that situation without the scientists
knowing.
Describe how organisms are placed in the Three Domain
(Woese-Fox) classification system vs how organisms are placed
in the Five Kingdom (Traditional Wittaker) classification system.
Which classification system is more useful to a microbiologist and
,2|Page
why? - ANSWER-Organisms are placed in the Three Domain
classification system by using the three main branches,
"Bacteria," Archaea," and "Eukarya." They are placed in each
domain based on what kind of cell they are (eukaryotic and
prokaryotic). Although prokaryotic cells are both Domain Bacteria
and Domain Archaea, the members of the Domain Archaea are
very different from the ones in Domain Bacteria as they are able
to live in severe environments and are also able to produce
metabolic byproducts.
Organisms are placed in the Five Kingdom classification system
by using certain levels that the organisms need to pass in order to
go on to the next level. The bottom level is the domain and the
organism works its way up to the top level, which is species.
It is more useful for a microbiologist to use the Three Domain
classification system because it classifies organisms into smaller
classifications rather than being broad. The Five Kingdom
classification system is more observation based while the Three
Domain classification system is more DNA based.
,3|Page
Why must an electron microscope be used to see most viruses?
Why can't they be seen using a light microscope? - ANSWER-An
electron microscope must be used to see most viruses because
viruses are too small to be seen by the optical microscope. The
electron microscope has a magnification of 5,000X to 1,000,000X
and it does not use light.
Viruses can't be seen using a light microscope because light
microscopes do not have as much magnification as the electron
microscope and you will not be able to see the viruses.
What is the difference between a mixed culture and a pure culture
of microbes? - ANSWER-The difference between a mixed culture
and a pure culture of microbes is that a mixed culture are multiple
species growing in a container while a pure culture is one species
growing in a container.
Mannitol Salt Agar and MacConkey Agar are two examples of
media that is both selective and differential. In your own words
describe what selective and differential mean. - ANSWER-
Selective- Contains one or more agents that restrain growth of a
certain microbe(s) but urge the growth of another.
, 4|Page
Differential- Allows several types of microbes to grow and show
differences among themselves.
All bacteria make humans ill. - ANSWER-False
In the three domain classification system, all prokaryotic cells are
grouped into Monera. - ANSWER-False
Angelina Hesse suggested adding ______ as a thickener to broth
in order to make solid media. - ANSWER-Agar
Koch's postulates were used - ANSWER-to definitively link one
microorganism to one disease.
In this class of microorganisms, all members are prokaryotes. -
ANSWER-bacteria
The theory that states life can arise from nonliving things and
would explain an infection by stating that first the body would be
