Microbiology Final Exam Newest Questions
and Answers (2026) | Comprehensive
Updated Review and Rationales | Grade A+
‣ Define Microbiology -✓✓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 -
✓✓**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 -✓✓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) -✓✓• 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) -
✓✓**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
**Abiogenesis - spontaneous generation. Early belief that some forms of life could arise
from vital forces present in nonliving or decomposing matter; Examples - flies from
manure; old rags & thrown out food = mice; broth left unrefrigerated became cloudy =
microbes
‣ Contributions of Koch (Koch - Which etiological agent Koch used with his postulates to
prove the germ theory of disease) -✓✓**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 -✓✓•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 -✓✓Microbes that normally live in or on a human and do not
cause disease
‣ Define Taxonomy -✓✓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
‣ Know order of the taxa -✓✓Know the order of taxa:
Largest to smallest
Did Green Popeye Come Over For Green Spinach?
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 -✓✓• 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 -✓✓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 -✓✓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 stain)
o 5: Information gathering - testing of cultures for biochemical and enzyme
characteristics and additionally with drug sensitivity, immunologic reactions, and genetic
makeup. (unknown #2)
o 6: Identification - results of tests and Bergey's Manual (microbiology bible) (used to
provide keys or charts) to identify the genus and species of the microorganism
‣ Define Pure Culture -✓✓One microbe growing on or in the culture medium
‣ Define Mixed Culture -✓✓More than one microbe growing in sample or culture
medium
‣ Physical types of media (solid, liquid, semisolid) -✓✓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 -
and Answers (2026) | Comprehensive
Updated Review and Rationales | Grade A+
‣ Define Microbiology -✓✓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 -
✓✓**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 -✓✓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) -✓✓• 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) -
✓✓**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
**Abiogenesis - spontaneous generation. Early belief that some forms of life could arise
from vital forces present in nonliving or decomposing matter; Examples - flies from
manure; old rags & thrown out food = mice; broth left unrefrigerated became cloudy =
microbes
‣ Contributions of Koch (Koch - Which etiological agent Koch used with his postulates to
prove the germ theory of disease) -✓✓**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 -✓✓•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 -✓✓Microbes that normally live in or on a human and do not
cause disease
‣ Define Taxonomy -✓✓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
‣ Know order of the taxa -✓✓Know the order of taxa:
Largest to smallest
Did Green Popeye Come Over For Green Spinach?
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 -✓✓• 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 -✓✓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 -✓✓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 stain)
o 5: Information gathering - testing of cultures for biochemical and enzyme
characteristics and additionally with drug sensitivity, immunologic reactions, and genetic
makeup. (unknown #2)
o 6: Identification - results of tests and Bergey's Manual (microbiology bible) (used to
provide keys or charts) to identify the genus and species of the microorganism
‣ Define Pure Culture -✓✓One microbe growing on or in the culture medium
‣ Define Mixed Culture -✓✓More than one microbe growing in sample or culture
medium
‣ Physical types of media (solid, liquid, semisolid) -✓✓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 -
