Microbiology Exam 1 2025:Mutiple choice Questions And Answers
_______ ______ cells have an outer membrane made up of lipopolysaccharide (LPS) - ansGram negative
_______ _________ cells contain two layers in their cell envelope - ansGram positive
___________ are considered to be unicellular organisms. ____________ and ___________are considered to be
unicellular or multicellular organisms. ____________ are considered to be multicellular organisms. Are plants
and animals considered to unicellular or multicellular organisms? - ans1. Protozoa
2. Fungi and Algae
3. Helminths
4. Plants and animals are considered unicellular
_____________ and ____________ are included in the kingdom Protista. Describe the major characteristics
regarding algae. True or false: All algae are pathogenic? Describe the major characteristics regarding protozoa.
What are the three organs of locomotion for protozoa. Do all protozoa have a trophozoite stage? Do all
protozoa produce cysts? What is the function of a protozoan cyst? True or false: All protozoa are pathogenic.
Name at least four pathogenic protozoa and the disease name. - ans
6 major groups of microorganisms - ans1. Bacteria
2. Algae
3. Protozoa
4. Helminths
5. Fungi
6. Viruses
A microscope has a total magnification of 850x when using the oil immersion objective lens. What is the power
of the ocular lens? - ans8500
A microscopic cluster of cells that originated from a single cell - ansColony
,Agricultural Microbiology - ans- Concerned with the relationship between microbes and domesticated plants
and animals
- Plant specialists focus on plant diseases, soil fertility, and nutritional interactions
- Animal specialists focus on infectious diseases and other associations animals have with microorganisms
Agricultural Microbiology - ans- Deals with the relationships between microbes and domesticated plants and
animals
- Plant specialists focus on plant diseases, soil fertility, and nutritional interactions
- Animal specialists work with infectious diseases and other associations animals have with microorganisms
Algae - ans- Unicellular microorganisms
- Prokaryotic
- Food or water borne
- Reproduce Asexually
- Photosythetic
Assay media - ansUsed to test the effectiveness of antimicrobial drugs
Bacteria - ans- Unicellular microorganisms
- Some cause human, animal, or plant diseases; others are beneficial.
- Prokaryotic
Bacteria and Archaea consist of what type of cells? - ansProkaryotic
Bergey's manual of ______________________ _______________________ is based on phenotypic
characteristics and is used in clinical, teaching, and research labs - ansDeterminative Bacteriology
,Bioremediation - ansIntroduction of microbes into the environment to restore stability or to clean up toxic
pollutants
Biotechnology - ansManipulation of microorganisms to make products in an industrial setting
Can a medium be classified as both selective and differential? - ansYes, some media can be both selective and
differential
Can antibiotics target viral infections? Explain your answer. - ansNo, because:
• Viruses mutate at a rapid rate
• Scientists focus on developing vaccines against viruses since few antiviral drugs are available and antibiotics
are ineffective
• Interferon (IFN)
- Naturally occurring human cell product
- Used with some success in treating viral infections
Carbohydrate fermentation media - ansContains sugars and pH indicators to show fermentation
Classification - ansAttempts the orderly arrangement of organisms into a hierarchy of taxa (categories)
Clostridium, Bacillus, and Sporosarcina produce dormant highly resistant __________ - ansEndospores
Consist of prokaryotic cells and Staphylococcus aureus and Escherichia Coli are examples of this organism -
ansBacteria
Contaminated Culture - ansContains contaminants or intruders
Contrast - ansDegree of contrast from the surroundings. Iris diaphragm controls the amount of light entering
the condenser
, Define nucleocapsid. - ans- Capsid
• Shell surrounds the nucleic acid
• Nucleocapsid: capsid and nucleic acid together
Describe the 3 different methods of isolating bacteria. - ans- Streak plate: a small droplet of culture or sample is
spread over the surface of the medium with an inoculating loop in a pattern that gradually thins out the sample
and separates the cells spatially over several sections of the plate
- Loop dilution: the sample is inoculated serially into a series of cooled but sill liquid agar tubes so as to dilute
the number of cells in each successive tube in the series.
- Spread plate: a small volume of liquid, diluted sample is pipetted onto the surface of the medium and spread
evenly by a sterile spreading tool
Describe the 3 physical states of media and the purpose of each - ans- Liquid: found in test tubes, termed
broths, milks, infusions
- Semi-solid: clot like, found in test tubes, determines motility of bacteria
- Solid: provide a firm surface on which cells can form discrete colonies
Describe the differences between Gram-positive and Gram-negative cells. - ansGram positive cells have a thick
layer of peptidoglycan 20-80nm thick and gram negative cells have a thin layer of peptidoglycan 1-3nm
Describe the different arrangements for bacterial flagella. - ans- Monotrichous polar: single flagellum
- Lophotrichous polar: several tufts emerging from same site
- Amphitrichous polar: flagella at both ends
- Petritichous: flagella randomly dispersed over the entire surface of the cell
Describe the different types of the bacterial glycocalyx, also known as the surface coating. - ansSlime layer -
_______ ______ cells have an outer membrane made up of lipopolysaccharide (LPS) - ansGram negative
_______ _________ cells contain two layers in their cell envelope - ansGram positive
___________ are considered to be unicellular organisms. ____________ and ___________are considered to be
unicellular or multicellular organisms. ____________ are considered to be multicellular organisms. Are plants
and animals considered to unicellular or multicellular organisms? - ans1. Protozoa
2. Fungi and Algae
3. Helminths
4. Plants and animals are considered unicellular
_____________ and ____________ are included in the kingdom Protista. Describe the major characteristics
regarding algae. True or false: All algae are pathogenic? Describe the major characteristics regarding protozoa.
What are the three organs of locomotion for protozoa. Do all protozoa have a trophozoite stage? Do all
protozoa produce cysts? What is the function of a protozoan cyst? True or false: All protozoa are pathogenic.
Name at least four pathogenic protozoa and the disease name. - ans
6 major groups of microorganisms - ans1. Bacteria
2. Algae
3. Protozoa
4. Helminths
5. Fungi
6. Viruses
A microscope has a total magnification of 850x when using the oil immersion objective lens. What is the power
of the ocular lens? - ans8500
A microscopic cluster of cells that originated from a single cell - ansColony
,Agricultural Microbiology - ans- Concerned with the relationship between microbes and domesticated plants
and animals
- Plant specialists focus on plant diseases, soil fertility, and nutritional interactions
- Animal specialists focus on infectious diseases and other associations animals have with microorganisms
Agricultural Microbiology - ans- Deals with the relationships between microbes and domesticated plants and
animals
- Plant specialists focus on plant diseases, soil fertility, and nutritional interactions
- Animal specialists work with infectious diseases and other associations animals have with microorganisms
Algae - ans- Unicellular microorganisms
- Prokaryotic
- Food or water borne
- Reproduce Asexually
- Photosythetic
Assay media - ansUsed to test the effectiveness of antimicrobial drugs
Bacteria - ans- Unicellular microorganisms
- Some cause human, animal, or plant diseases; others are beneficial.
- Prokaryotic
Bacteria and Archaea consist of what type of cells? - ansProkaryotic
Bergey's manual of ______________________ _______________________ is based on phenotypic
characteristics and is used in clinical, teaching, and research labs - ansDeterminative Bacteriology
,Bioremediation - ansIntroduction of microbes into the environment to restore stability or to clean up toxic
pollutants
Biotechnology - ansManipulation of microorganisms to make products in an industrial setting
Can a medium be classified as both selective and differential? - ansYes, some media can be both selective and
differential
Can antibiotics target viral infections? Explain your answer. - ansNo, because:
• Viruses mutate at a rapid rate
• Scientists focus on developing vaccines against viruses since few antiviral drugs are available and antibiotics
are ineffective
• Interferon (IFN)
- Naturally occurring human cell product
- Used with some success in treating viral infections
Carbohydrate fermentation media - ansContains sugars and pH indicators to show fermentation
Classification - ansAttempts the orderly arrangement of organisms into a hierarchy of taxa (categories)
Clostridium, Bacillus, and Sporosarcina produce dormant highly resistant __________ - ansEndospores
Consist of prokaryotic cells and Staphylococcus aureus and Escherichia Coli are examples of this organism -
ansBacteria
Contaminated Culture - ansContains contaminants or intruders
Contrast - ansDegree of contrast from the surroundings. Iris diaphragm controls the amount of light entering
the condenser
, Define nucleocapsid. - ans- Capsid
• Shell surrounds the nucleic acid
• Nucleocapsid: capsid and nucleic acid together
Describe the 3 different methods of isolating bacteria. - ans- Streak plate: a small droplet of culture or sample is
spread over the surface of the medium with an inoculating loop in a pattern that gradually thins out the sample
and separates the cells spatially over several sections of the plate
- Loop dilution: the sample is inoculated serially into a series of cooled but sill liquid agar tubes so as to dilute
the number of cells in each successive tube in the series.
- Spread plate: a small volume of liquid, diluted sample is pipetted onto the surface of the medium and spread
evenly by a sterile spreading tool
Describe the 3 physical states of media and the purpose of each - ans- Liquid: found in test tubes, termed
broths, milks, infusions
- Semi-solid: clot like, found in test tubes, determines motility of bacteria
- Solid: provide a firm surface on which cells can form discrete colonies
Describe the differences between Gram-positive and Gram-negative cells. - ansGram positive cells have a thick
layer of peptidoglycan 20-80nm thick and gram negative cells have a thin layer of peptidoglycan 1-3nm
Describe the different arrangements for bacterial flagella. - ans- Monotrichous polar: single flagellum
- Lophotrichous polar: several tufts emerging from same site
- Amphitrichous polar: flagella at both ends
- Petritichous: flagella randomly dispersed over the entire surface of the cell
Describe the different types of the bacterial glycocalyx, also known as the surface coating. - ansSlime layer -
