MICROBIOLOGY - COMPREHENSIVE FINAL EXAM QUESTIONS AND ANSWERS 2025
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
**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
,MICROBIOLOGY - COMPREHENSIVE FINAL EXAM QUESTIONS AND ANSWERS 2025
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
,MICROBIOLOGY - COMPREHENSIVE FINAL EXAM QUESTIONS AND ANSWERS 2025
o Nomenclature - assigning names
o Identification - determining and recording traits of organisms for placement into taxonomic schemes
Know order of the taxa - (ANSWER)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 - (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)
, MICROBIOLOGY - COMPREHENSIVE FINAL EXAM QUESTIONS AND ANSWERS 2025
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 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 - (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%)
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
**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
,MICROBIOLOGY - COMPREHENSIVE FINAL EXAM QUESTIONS AND ANSWERS 2025
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
,MICROBIOLOGY - COMPREHENSIVE FINAL EXAM QUESTIONS AND ANSWERS 2025
o Nomenclature - assigning names
o Identification - determining and recording traits of organisms for placement into taxonomic schemes
Know order of the taxa - (ANSWER)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 - (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)
, MICROBIOLOGY - COMPREHENSIVE FINAL EXAM QUESTIONS AND ANSWERS 2025
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 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 - (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%)
