Microbiology Unit one test

from the study guide

Chapter 1 — What are the six major microbial groups listed on the study guide? A. Bacteria, Archaea, Fungi, Protozoa, Helminths, and Viruses B. Bacteria, Plants, Animals, Fungi, Archaea, and Viruses C. Bacteria, Archaea, Plants, Animals, Protozoa, and Prions D. Fungi, Helminths, Plants, Animals, Viruses, and Archaea

A. Bacteria, Archaea, Fungi, Protozoa, Helminths, and Viruses

Chapter 1 — Which two microbial groups are prokaryotic? A. Bacteria and Archaea B. Fungi and Protozoa C. Helminths and Fungi D. Protozoa and Viruses

A. Bacteria and Archaea

Chapter 1 — Which microbial groups are eukaryotic? A. Bacteria and Archaea B. Fungi, Protozoa, and Helminths C. Bacteria and Viruses D. Archaea and Viruses

B. Fungi, Protozoa, and Helminths

Chapter 1 — Which group is non-cellular? A. Bacteria B. Fungi C. Viruses D. Protozoa

C. Viruses

Chapter 1 — Which group consists of multicellular parasitic worms? A. Protozoa B. Helminths C. Archaea D. Bacteria

B. Helminths

Chapter 1 — Which group includes organisms that are usually unicellular eukaryotes? A. Protozoa B. Helminths C. Bacteria D. Archaea

A. Protozoa

Chapter 1 — Which statement best describes bacteria? A. Eukaryotic and multicellular B. Prokaryotic and cellular C. Non-cellular D. Eukaryotic and always multicellular

B. Prokaryotic and cellular

Chapter 1 — Which statement best describes Archaea? A. Prokaryotic organisms distinct from bacteria B. Multicellular eukaryotes C. Non-cellular particles D. Parasitic worms

A. Prokaryotic organisms distinct from bacteria

Chapter 1 — Which statement best describes fungi? A. Prokaryotic organisms B. Eukaryotic organisms that include yeasts and molds C. Non-cellular organisms D. Bacterial parasites

B. Eukaryotic organisms that include yeasts and molds

Chapter 1 — Which statement best describes viruses? A. They are prokaryotic cells B. They are eukaryotic cells C. They are non-cellular D. They are multicellular

C. They are non-cellular

Chapter 1 — Would "a microscopic, living organism" be a complete definition of a microbe? A. Yes, because all microbes are living cells B. No, because some microbes such as viruses are non-cellular C. Yes, because viruses are bacteria D. No, because microbes are never microscopic

B. No, because some microbes such as viruses are non-cellular

Chapter 1 — What is one major difference between prokaryotes and eukaryotes? A. Prokaryotes have membrane-bound nuclei B. Eukaryotes have membrane-bound nuclei C. Prokaryotes lack DNA D. Eukaryotes lack ribosomes

B. Eukaryotes have membrane-bound nuclei

Chapter 1 — Which cell type generally lacks membrane-bound organelles? A. Prokaryotic B. Eukaryotic C. Fungal D. Animal

A. Prokaryotic

Chapter 1 — Which cell type generally has membrane-bound organelles? A. Prokaryotic B. Eukaryotic C. Bacterial D. Archaeal

B. Eukaryotic

Chapter 1 — What is binomial nomenclature? A. A two-part system for naming organisms B. A system for classifying cells by shape C. A method for staining bacteria D. A method for identifying pathogens

A. A two-part system for naming organisms

Chapter 1 — What are the two parts of a binomial scientific name? A. Kingdom and phylum B. Genus and species epithet C. Family and genus D. Domain and kingdom

B. Genus and species epithet

Chapter 1 — In Escherichia coli, what is Escherichia? A. Species epithet B. Genus C. Family D. Domain

B. Genus

Chapter 1 — In Escherichia coli, what is coli? A. Genus B. Family C. Species epithet D. Domain

C. Species epithet

Chapter 1 — Which part of a scientific name is capitalized? A. Species epithet B. Genus C. Both words D. Neither

B. Genus

Chapter 1 — What is a microbiome? A. A single pathogen B. A community of microorganisms associated with a host or environment C. The host's DNA D. A bacterial cell wall

B. A community of microorganisms associated with a host or environment

Chapter 1 — What are the two primary methods used to classify microbes according to the study guide? A. Phenotypic characteristics and genetic/molecular comparisons B. Gram staining and fermentation only C. Cell size and color only D. Motility and oxygen use only

A. Phenotypic characteristics and genetic/molecular comparisons

Chapter 1 — What can genetic sequence comparisons help determine? A. Evolutionary relationships and classification B. Only cell size C. Only cell shape D. Whether a cell has a nucleus

A. Evolutionary relationships and classification

Chapter 1 — What complication can result from using a 97% sequence-similarity cutoff? A. Closely related organisms may be incorrectly grouped or separated B. All organisms become identical C. It prevents DNA sequencing D. It identifies every strain perfectly

A. Closely related organisms may be incorrectly grouped or separated

Chapter 1 — What is mutualism? A. Both organisms benefit B. One benefits and the other is harmed C. One benefits and the other is unaffected D. Both are harmed

A. Both organisms benefit

Chapter 1 — What is commensalism? A. Both organisms benefit B. One benefits while the other is essentially unaffected C. One benefits while the other is harmed D. Both organisms are harmed

B. One benefits while the other is essentially unaffected

Chapter 1 — What is parasitism? A. Both organisms benefit B. One benefits while the host is harmed C. One benefits while the host is unaffected D. Neither benefits

B. One benefits while the host is harmed

Chapter 1 — Which symbiotic interaction is commonly found in a healthy microbiome? A. Mutualism B. Parasitism C. Predation D. Competition

A. Mutualism

Chapter 1 — What is a true pathogen? A. An organism that normally causes disease in a healthy host B. An organism that only causes disease in immunocompromised hosts C. An organism that never causes disease D. A beneficial microbiome member

A. An organism that normally causes disease in a healthy host

Chapter 1 — What is an opportunistic pathogen? A. An organism that can cause disease when host conditions allow it B. An organism that always causes disease C. An organism that cannot live in humans D. A beneficial organism only

A. An organism that can cause disease when host conditions allow it

Chapter 1 — Can a healthy person's microbiome contain opportunistic pathogens? A. Yes, some may be present without causing disease B. No, all opportunists must be eliminated C. Only viruses can be present D. Only helminths can be present

A. Yes, some may be present without causing disease

Chapter 1 — What is dysbiosis? A. Normal microbial balance B. Disruption or imbalance of the microbiome C. Bacterial reproduction D. Viral replication

B. Disruption or imbalance of the microbiome

Chapter 1 — What are host factors? A. Characteristics of the host that can affect microbial colonization or disease B. Characteristics found only in bacteria C. Bacterial cell-wall components D. Viral structures

A. Characteristics of the host that can affect microbial colonization or disease

Chapter 1 — Why does microbe location matter in determining whether a microbe causes disease? A. A microbe can be harmless in one body location but harmful in another B. Location never matters C. All body sites have identical microbiota D. Only viruses are location-dependent

A. A microbe can be harmless in one body location but harmful in another

Chapter 1 — What does planktonic mean? A. Microbes growing freely rather than attached in a biofilm B. Microbes inside a nucleus C. Microbes forming endospores D. Microbes growing only on plants

A. Microbes growing freely rather than attached in a biofilm

Chapter 1 — What is a biofilm? A. A single bacterial cell B. A community of microorganisms attached to a surface and associated with a matrix C. A virus D. A sterile surface

B. A community of microorganisms attached to a surface and associated with a matrix

Chapter 1 — Why do bacteria form biofilms? A. To live in a favorable environment and gain protection B. To become viruses C. To lose their DNA D. To stop interacting with other cells

A. To live in a favorable environment and gain protection

Chapter 1 — Why are biofilms medically important? A. They can contribute to persistent infections and make microbes harder to eradicate B. They eliminate pathogens C. They prevent microbial growth D. They are always harmless

A. They can contribute to persistent infections and make microbes harder to eradicate

Chapter 1 — Which form is generally more difficult to eradicate? A. Planktonic B. Biofilm C. Both are always identical D. Neither

B. Biofilm

Chapter 1 — Which statement best explains why biofilms can be difficult to treat? A. The biofilm environment can protect microbes from treatment and host defenses B. Biofilms contain no living cells C. Biofilms have no extracellular material D. Antibiotics cannot enter any liquid

A. The biofilm environment can protect microbes from treatment and host defenses

Chapter 1 — What was the purpose of the Human Microbiome Project? A. To study microorganisms associated with the human body B. To eliminate all human microbes C. To classify only viruses D. To make humans sterile

A. To study microorganisms associated with the human body

Chapter 1 — What does germ theory state? A. Microorganisms can cause infectious diseases B. All microorganisms are harmful C. Disease comes only from genetics D. Microorganisms cannot cause disease

A. Microorganisms can cause infectious diseases

Chapter 1 — What are Koch's postulates designed to help establish? A. A relationship between a particular microorganism and a particular disease B. The shape of a bacterial cell C. The size of a virus D. The taxonomy of fungi

A. A relationship between a particular microorganism and a particular disease

Chapter 1 — Which is a limitation of Koch's postulates? A. Some pathogens cannot be grown easily in pure culture B. Every pathogen grows easily C. Every disease has exactly one pathogen D. Viruses grow on ordinary agar

A. Some pathogens cannot be grown easily in pure culture

Chapter 1 — Why are viruses a problem for traditional Koch's postulates? A. They require host cells for replication B. They are too large C. They have peptidoglycan D. They are fungi

A. They require host cells for replication

Chapter 1 — What is taxonomy? A. Classification of organisms B. Treatment of disease C. Bacterial reproduction D. Protein synthesis

A. Classification of organisms

Chapter 3 — What are the two prokaryotic domains? A. Bacteria and Archaea B. Fungi and Protista C. Animalia and Plantae D. Viruses and Eukarya

A. Bacteria and Archaea

Chapter 3 — Why are prokaryotic cells generally small? A. Their small size provides a high surface-area-to-volume ratio B. They have no plasma membrane C. They have no DNA D. They are multicellular

A. Their small size provides a high surface-area-to-volume ratio

Chapter 3 — What is the approximate size range given for many prokaryotic cells? A. 0.5–5 μm B. 50–500 μm C. 5–50 mm D. 0.01–0.05 mm

A. 0.5–5 μm

Chapter 3 — What shape is a coccus? A. Spherical B. Rod-shaped C. Comma-shaped D. Spiral

A. Spherical

Chapter 3 — What shape is a bacillus? A. Spherical B. Rod-shaped C. Comma-shaped D. Corkscrew

A. Rod-shaped

Chapter 3 — What shape is a vibrio? A. Comma-shaped B. Spherical C. Rod-shaped D. Corkscrew

A. Comma-shaped

Chapter 3 — What shape is a spirillum? A. Rigid spiral B. Sphere C. Rod D. Comma

A. Rigid spiral

Chapter 3 — What shape is a spirochete? A. Flexible corkscrew/spiral B. Sphere C. Rod D. Comma

A. Flexible corkscrew/spiral

Chapter 3 — What does pleomorphic mean? A. Able to change shape B. Unable to reproduce C. Lacking DNA D. Lacking a membrane

A. Able to change shape

Chapter 3 — What are diplococci? A. Pairs of cocci B. Chains of cocci C. Clusters of cocci D. Chains of rods

A. Pairs of cocci

Chapter 3 — What are streptococci? A. Chains of cocci B. Pairs of cocci C. Clusters of rods D. Pairs of rods

A. Chains of cocci

Chapter 3 — What are staphylococci? A. Grape-like clusters of cocci B. Chains of cocci C. Pairs of rods D. Chains of rods

A. Grape-like clusters of cocci

Chapter 3 — What are diplobacilli? A. Pairs of rods B. Chains of rods C. Pairs of cocci D. Clusters of cocci

A. Pairs of rods

Chapter 3 — What are streptobacilli? A. Chains of rods B. Pairs of rods C. Clusters of cocci D. Pairs of cocci

A. Chains of rods

Chapter 3 — What is binary fission? A. Asexual reproduction in which a prokaryotic cell divides B. Sexual reproduction C. Viral replication D. Endospore formation

A. Asexual reproduction in which a prokaryotic cell divides

Chapter 3 — What happens first during binary fission? A. The chromosome is replicated B. The cell forms a nucleus C. The cell forms gametes D. The cell produces an endospore

A. The chromosome is replicated

Chapter 3 — What is the outcome of binary fission? A. Two daughter cells B. Four haploid cells C. One endospore D. Two nuclei

A. Two daughter cells

Chapter 3 — Does binary fission use spores for reproduction? A. Yes B. No C. Only in Gram-positive bacteria D. Only in Archaea

B. No

Chapter 3 — Is binary fission sexual or asexual? A. Sexual B. Asexual C. Both D. Neither

B. Asexual

Chapter 3 — Which genera can produce endospores and are medically relevant? A. Bacillus and Clostridium B. Escherichia and Staphylococcus C. Mycoplasma and Vibrio D. Spirillum and Neisseria

A. Bacillus and Clostridium

Chapter 3 — What is the main function of an endospore? A. Survival during unfavorable conditions B. Reproduction C. Motility D. Protein synthesis

A. Survival during unfavorable conditions

Chapter 3 — Are endospores reproductive structures? A. Yes B. No, they are survival structures C. Only in fungi D. Only in viruses

B. No, they are survival structures

Chapter 3 — Which bacterial type has a thick peptidoglycan layer? A. Gram-positive B. Gram-negative C. Mycoplasma D. L-form

A. Gram-positive

Chapter 3 — Which bacterial type has a thin peptidoglycan layer and an outer membrane? A. Gram-positive B. Gram-negative C. Mycoplasma D. L-form

B. Gram-negative

Chapter 3 — What is LPS? A. Lipopolysaccharide found in the Gram-negative outer membrane B. A Gram-positive wall protein C. A fungal wall component D. A viral protein

A. Lipopolysaccharide found in the Gram-negative outer membrane

Chapter 3 — Which part of LPS is associated with endotoxin activity? A. Lipid A B. O antigen C. Peptidoglycan D. Teichoic acid

A. Lipid A

Chapter 3 — What are teichoic acids associated with? A. Gram-positive cell walls B. Gram-negative outer membranes C. Fungal walls D. Viral envelopes

A. Gram-positive cell walls

Chapter 3 — What are mycolic acids associated with? A. Acid-fast bacteria B. Gram-negative bacteria only C. Mycoplasma D. Fungi

A. Acid-fast bacteria

Chapter 3 — Why are acid-fast bacteria difficult to stain? A. Their waxy, mycolic-acid-rich cell wall resists ordinary staining/decolorization B. They lack DNA C. They have no membrane D. They have a cellulose wall

A. Their waxy, mycolic-acid-rich cell wall resists ordinary staining/decolorization

Chapter 3 — Why can acid-fast bacteria be difficult to treat? A. Their unusual cell-wall structure can limit drug penetration and contribute to resistance B. They have no DNA C. They have chloroplasts D. They are viruses

A. Their unusual cell-wall structure can limit drug penetration and contribute to resistance

Chapter 3 — Why do Mycoplasma species naturally resist penicillin? A. They lack a cell wall/peptidoglycan target B. They have an extra-thick wall C. They are viruses D. They have chloroplasts

A. They lack a cell wall/peptidoglycan target

Chapter 3 — What are L-forms? A. Bacterial forms that lack a cell wall B. Viral particles C. Fungal spores D. Endospores

A. Bacterial forms that lack a cell wall

Chapter 3 — What is the correct Gram-stain order? A. Crystal violet → iodine → decolorizer → counterstain B. Iodine → crystal violet → safranin → decolorizer C. Safranin → iodine → crystal violet → alcohol D. Crystal violet → safranin → iodine → decolorizer

A. Crystal violet → iodine → decolorizer → counterstain

Chapter 3 — What is the primary stain in the Gram stain? A. Crystal violet B. Iodine C. Decolorizer D. Safranin

A. Crystal violet

Chapter 3 — What is the mordant in the Gram stain? A. Crystal violet B. Iodine C. Decolorizer D. Safranin

B. Iodine

Chapter 3 — What is the purpose of the decolorizer? A. Removes the crystal violet-iodine complex from Gram-negative cells more readily B. Stains all cells purple C. Forms peptidoglycan D. Stains cells green

A. Removes the crystal violet-iodine complex from Gram-negative cells more readily

Chapter 3 — What is the counterstain in the Gram stain? A. Safranin B. Iodine C. Crystal violet D. Alcohol

A. Safranin

Chapter 3 — What color do Gram-positive bacteria appear after Gram staining? A. Purple B. Pink/red C. Green D. Colorless

A. Purple

Chapter 3 — What color do Gram-negative bacteria appear after Gram staining? A. Purple B. Pink/red C. Green D. Black

B. Pink/red

Chapter 3 — Why is the Gram stain useful when treating infections? A. It provides rapid information about bacterial type and can help guide treatment B. It identifies every bacterial species immediately C. It kills all bacteria D. It replaces susceptibility testing

A. It provides rapid information about bacterial type and can help guide treatment

Chapter 3 — What is the purpose of transporting materials into and out of cells? A. To obtain nutrients, remove wastes, and maintain cellular conditions B. To make cells multicellular C. To eliminate DNA D. To produce endospores

A. To obtain nutrients, remove wastes, and maintain cellular conditions

Chapter 3 — Is simple diffusion passive or active? A. Passive B. Active C. Both D. Neither

A. Passive

Chapter 3 — Is osmosis passive or active? A. Passive B. Active C. Both D. Neither

A. Passive

Chapter 3 — Is primary active transport passive or active? A. Passive B. Active C. Both D. Neither

B. Active

Chapter 3 — Is secondary active transport passive or active? A. Passive B. Active C. Both D. Neither

B. Active

Chapter 3 — Is the phosphotransferase system an active transport mechanism? A. Yes B. No C. Only in Archaea D. Only in fungi

A. Yes

Chapter 3 — Which transport mechanism directly requires ATP? A. Primary active transport B. Simple diffusion C. Osmosis D. Facilitated diffusion

A. Primary active transport

Chapter 3 — Which transport mechanism uses an existing ion gradient rather than directly using ATP at the transporter? A. Secondary active transport B. Simple diffusion C. Osmosis D. Phagocytosis

A. Secondary active transport

Chapter 3 — What is diffusion? A. Movement down a concentration gradient B. Movement against a gradient using ATP C. Movement of DNA between cells D. Cell division

A. Movement down a concentration gradient

Chapter 3 — What is osmosis? A. Movement of water across a selectively permeable membrane B. Movement of proteins into ribosomes C. Movement of DNA D. Movement of cells

A. Movement of water across a selectively permeable membrane

Chapter 3 — What is the fluid mosaic model? A. A model describing the plasma membrane as a fluid phospholipid bilayer containing proteins B. A model of bacterial DNA C. A model of binary fission D. A model of endospore formation

A. A model describing the plasma membrane as a fluid phospholipid bilayer containing proteins

Chapter 3 — Which part of a phospholipid is hydrophilic? A. Phosphate-containing head B. Fatty-acid tails C. Hydrocarbon tails D. Sterol tail

A. Phosphate-containing head

Chapter 3 — Which part of a phospholipid is hydrophobic? A. Phosphate head B. Fatty-acid tails C. Carbohydrate head D. Protein channel

B. Fatty-acid tails

Chapter 3 — Why are membrane proteins important? A. They can function in transport, communication, and other cellular processes B. They only store DNA C. They make endospores D. They replace the phospholipid bilayer

A. They can function in transport, communication, and other cellular processes

Chapter 3 — Which substances generally cross the lipid portion of the membrane most easily? A. Small nonpolar molecules B. Large proteins C. Charged ions D. DNA

A. Small nonpolar molecules