Microbiology - Comprehensive Final
Exam Questions And All Correct
Answers.
Define Microbiology - Answer Study of living organisms & acellular biological entities too small
to be seen without the aid of a microscope; study of microorganisms
Types of organisms studied in microbiology & their branches of microbiology - Answer
**Living organisms:
o Bacteria - unicellular organisms
o Algae - unicellular organism that photosynthesize (does not cause disease)
o Protozoa - unicellular organism that are animal-like
o Fungi - unicellular or multicellular organisms (yeast or molds)
o Helminths - multicellular eukaryotic worms
**Acellular organisms (not alive):
o Viruses - infectious agents composed of protein and nucleic acid, must invade host cell to
multiply
o Viroids - infectious agents composed of only RNA (ribonucleic acid)
o Prions - infectious protiens (cause mad cow disease)
Distinguish between prokaryotic & eukaryotic - Answer Prokaryotic - no nuclues; 1 peice of
DNA; no membrane bound organelles; includes all bacteria
Eukaryotic - nucleus; many pieces of chromosomal DNA; membrane bound organelles; includes
protistans, fungi, plantae; animalia
2 metric scales used to measure both bacteria & viruses (um & nm) - Answer • Bacteria are
measured with the micrometer scale
• Viruses are measured with the nanometer scale
2 theories on how living things arise (spontaneous generation & bio-genesis) - Answer
**Biogenesis - the idea that living things can only arise from other living things (of the same
kind); Examples - mice from mice; dogs from dogs; bacteria from bacteria
,Contributions of Koch (Koch - Which etiological agent Koch used with his postulates to prove the
germ theory of disease) - Answer **Koch's contributions to microbiology:
• Proved that germ theory of disease by finding the causative agent for Anthrax (Bacillus
anthracis)
• Created Koch's Postulates -
o Microbe must be present in every case of the disease but absent from healthy organisms
o The suspected microbe must be isolated and grown in pure culture
o The same disease must result when the isolated microbe inoculated into a healthy host
o The same microbe must be isolated again from the disease host
• Developed many of the lab techniques still used for lab today
o Developed culture media
o Developed dishware
o Developed methods for isolation
**Which organism did Koch first identify as an etiological agent of a disease?
• Bacillus anthracis - causative agent for Anthrax
Define Pathogen - Answer •Pathogen - Microorganism that can cause disease in the normal
healthy individual
•Parasite - microorganisms that live on or in the body of another organism
•Host - other organism that the parasite is living on or in
Define Normal Flora - Answer Microbes that normally live in or on a human and do not cause
disease
Define Taxonomy - Answer What is taxonomy?
• Formal system for organizing, classifying and naming living things
• Originated by Carl Von Linne (Carolus Linneaus)
• Concerned with:
o Classification - orderly arrangement of organisms into 8 taxa groups
o Nomenclature - assigning names
o Identification - determining and recording traits of organisms for placement into taxonomic
schemes
,o Domain
o Kingdom
o Phylum
o Class
o Order
o Family
o Genus
o Species
Which Domains or Kingdoms contain prokaryotic or eukaryotic organisms that we studied over
the semester - Answer • Domain Bacteria - only prokaryotic organisms
• Domain Archaea - only prokaryotic organisms
• Domain Eukarya - only eukaryotic organisms
• Kingdom - Monera - only prokaryotic organisms
• Kingdoms Protista, Fungi, Plantae, Animalia - only eukaryotic organisms
How to write scientific name - Answer What is the binomial system?
Naming system that uses 2 names (genus and species)
• Genus - written first and capitalized
• Species - written second and lowercase
• If typed, both are italicized. If hand written, both are underlined.
Example - Staphylococcus aureus (S. aureus)
Inspiration for names is extremely varied and often imaginative
List & describe 5 I's - Answer o 1: Inoculation - introduction of a sample into a container of
media to produce a culture of observable growth. Virus need live cells to grow - use bird
embryo to grow viruses)
o 2: Incubation - the placement of the inoculated media in a specific temperature for a set time
to allow growth of the bacteria. 37C/98.6F optimal temp
o 3: Isolation - isolate a single colony on a petri plate to obtain a pure culture (streak plate, pour
plate, spread plate)
o 4: Inspection - observe the cultures for macroscopic growth of the bacteria, observe
microscopically for results of stains (used for unknown #1; gram stain, endospore stain, acid/fast
, Define Pure Culture - Answer One microbe growing on or in the culture medium
Define Mixed Culture - Answer More than one microbe growing in sample or culture medium
Physical types of media (solid, liquid, semisolid) - Answer Liquid media -
• Consistency like water; usually a broth (used in unknown #2)
• Used in test tube
• Contains no gelling agent = no agar
• Examples - nutrient broth, nitrate broth
Semisolid media -
• Used only for motility test
• Has a soft consistency
• Used in test tube
• Contains a small amount of agar (.3%-.5%)
• Examples - motility agar
Solid media -
Solid - provides a firm surface for colony formation
• Used in test tube or petri plate
• Contains larger amount of agar (1%-5%)
• Examples - nutrient sugar, TSA
What is agar & what organism is from & who suggested its use in the lab - Answer **What is
agar and what organism is used to make it?
• Agar is a complex polysaccharide isolated from the red algae - Gelidium
• They first tried using potatoes but potatoes became too mushy
o First used in Robert Koch's lab; Walther Hesse was his lab assistant; Fanny Hesse (Walther's
wife) suggested the use of agar in the lab.
**Whose lab was agar introduced into and who suggested agar as a possible gelling agent for
Exam Questions And All Correct
Answers.
Define Microbiology - Answer Study of living organisms & acellular biological entities too small
to be seen without the aid of a microscope; study of microorganisms
Types of organisms studied in microbiology & their branches of microbiology - Answer
**Living organisms:
o Bacteria - unicellular organisms
o Algae - unicellular organism that photosynthesize (does not cause disease)
o Protozoa - unicellular organism that are animal-like
o Fungi - unicellular or multicellular organisms (yeast or molds)
o Helminths - multicellular eukaryotic worms
**Acellular organisms (not alive):
o Viruses - infectious agents composed of protein and nucleic acid, must invade host cell to
multiply
o Viroids - infectious agents composed of only RNA (ribonucleic acid)
o Prions - infectious protiens (cause mad cow disease)
Distinguish between prokaryotic & eukaryotic - Answer Prokaryotic - no nuclues; 1 peice of
DNA; no membrane bound organelles; includes all bacteria
Eukaryotic - nucleus; many pieces of chromosomal DNA; membrane bound organelles; includes
protistans, fungi, plantae; animalia
2 metric scales used to measure both bacteria & viruses (um & nm) - Answer • Bacteria are
measured with the micrometer scale
• Viruses are measured with the nanometer scale
2 theories on how living things arise (spontaneous generation & bio-genesis) - Answer
**Biogenesis - the idea that living things can only arise from other living things (of the same
kind); Examples - mice from mice; dogs from dogs; bacteria from bacteria
,Contributions of Koch (Koch - Which etiological agent Koch used with his postulates to prove the
germ theory of disease) - Answer **Koch's contributions to microbiology:
• Proved that germ theory of disease by finding the causative agent for Anthrax (Bacillus
anthracis)
• Created Koch's Postulates -
o Microbe must be present in every case of the disease but absent from healthy organisms
o The suspected microbe must be isolated and grown in pure culture
o The same disease must result when the isolated microbe inoculated into a healthy host
o The same microbe must be isolated again from the disease host
• Developed many of the lab techniques still used for lab today
o Developed culture media
o Developed dishware
o Developed methods for isolation
**Which organism did Koch first identify as an etiological agent of a disease?
• Bacillus anthracis - causative agent for Anthrax
Define Pathogen - Answer •Pathogen - Microorganism that can cause disease in the normal
healthy individual
•Parasite - microorganisms that live on or in the body of another organism
•Host - other organism that the parasite is living on or in
Define Normal Flora - Answer Microbes that normally live in or on a human and do not cause
disease
Define Taxonomy - Answer What is taxonomy?
• Formal system for organizing, classifying and naming living things
• Originated by Carl Von Linne (Carolus Linneaus)
• Concerned with:
o Classification - orderly arrangement of organisms into 8 taxa groups
o Nomenclature - assigning names
o Identification - determining and recording traits of organisms for placement into taxonomic
schemes
,o Domain
o Kingdom
o Phylum
o Class
o Order
o Family
o Genus
o Species
Which Domains or Kingdoms contain prokaryotic or eukaryotic organisms that we studied over
the semester - Answer • Domain Bacteria - only prokaryotic organisms
• Domain Archaea - only prokaryotic organisms
• Domain Eukarya - only eukaryotic organisms
• Kingdom - Monera - only prokaryotic organisms
• Kingdoms Protista, Fungi, Plantae, Animalia - only eukaryotic organisms
How to write scientific name - Answer What is the binomial system?
Naming system that uses 2 names (genus and species)
• Genus - written first and capitalized
• Species - written second and lowercase
• If typed, both are italicized. If hand written, both are underlined.
Example - Staphylococcus aureus (S. aureus)
Inspiration for names is extremely varied and often imaginative
List & describe 5 I's - Answer o 1: Inoculation - introduction of a sample into a container of
media to produce a culture of observable growth. Virus need live cells to grow - use bird
embryo to grow viruses)
o 2: Incubation - the placement of the inoculated media in a specific temperature for a set time
to allow growth of the bacteria. 37C/98.6F optimal temp
o 3: Isolation - isolate a single colony on a petri plate to obtain a pure culture (streak plate, pour
plate, spread plate)
o 4: Inspection - observe the cultures for macroscopic growth of the bacteria, observe
microscopically for results of stains (used for unknown #1; gram stain, endospore stain, acid/fast
, Define Pure Culture - Answer One microbe growing on or in the culture medium
Define Mixed Culture - Answer More than one microbe growing in sample or culture medium
Physical types of media (solid, liquid, semisolid) - Answer Liquid media -
• Consistency like water; usually a broth (used in unknown #2)
• Used in test tube
• Contains no gelling agent = no agar
• Examples - nutrient broth, nitrate broth
Semisolid media -
• Used only for motility test
• Has a soft consistency
• Used in test tube
• Contains a small amount of agar (.3%-.5%)
• Examples - motility agar
Solid media -
Solid - provides a firm surface for colony formation
• Used in test tube or petri plate
• Contains larger amount of agar (1%-5%)
• Examples - nutrient sugar, TSA
What is agar & what organism is from & who suggested its use in the lab - Answer **What is
agar and what organism is used to make it?
• Agar is a complex polysaccharide isolated from the red algae - Gelidium
• They first tried using potatoes but potatoes became too mushy
o First used in Robert Koch's lab; Walther Hesse was his lab assistant; Fanny Hesse (Walther's
wife) suggested the use of agar in the lab.
**Whose lab was agar introduced into and who suggested agar as a possible gelling agent for
