CHAPTER 4
In which of the following circumstances do microbes act as a group? Multiple choice question. when assembled in a biofilm when forming endospores when a capsule is present when inclusion bodies are present
when assembled in a biofilm
Which two of the following situations are opportunities for microbes to act as a group rather than as individuals? Multiple select question. when nanowires are present when forming endospores in a biofilm
when nanowires are present in a biofilm
______ only have ribosomes that are 70S (Svedbergs) in size.
Archaea Bacteria
Which three structures comprise a bacterial flagellum? Periplasmic space Centrioles Basal body Filament Hook
Basal body Filament Hook
What structure is used in the Bergey's Manual of Determinative Bacteriology to divide bacteria and archaea into four major divisions?
Cell wall
Bacterial DNA is organized into which of the following tightly wound discrete units? Chromosomes Nuclear regions Genomes Genes
Chromosomes
Three genera of pathogenic bacteria that form endospores are ________,________- , and Sporosarcina.
Clostridium Bacillus
Which of the following are medically relevant endospore-producing genera? Escherichia Mycobacterium Clostridium Bacillus
Clostridium Bacillus
What is the correct term for describing very short, ovoid, rod-shaped bacterial cells?
Coccobacilli
What internal structure contributes to cell shape and division?
Cytoskeleton
Multiple Choice Question Which of the following statements concerning biofilm is correct? Multiple choice question. BIofilms form on substances when the surface is dry and devoid of organic matter. Biofilms have a uniform thickness and texture that is characteristic of each organism. DNA molecules may be present in biofilms as an attractant to more cells.
DNA molecules may be present in biofilms as an attractant to more cells.
Which scheme of classification focuses on characteristics such as morphology and physiological traits instead of phylogenetic relationships and nomenclature?
Diagnostic
Which two domains are the most closely related? Domain Bacteria Domain Archaea Domain Eukarya
Domain Archaea Domain Eukarya
Domain Archaea is most closely related to Domain______-because they share rRNA sequences and similar ribosomal structures.
Eukarya
True or false: The different coccal arrangements are a consequence of growth in broth or on solid media.
False
Which appendage(s) provide motility? Flagellum Glycocalyx Fimbriae Axial filaments
Flagellum Axial filaments
Which two of the following statements regarding bacterial ribosomes are correct? Ribosomes are usually attached to the endoplasmic reticulum, giving it its "rough" appearance. Ribosomes can be readily observed in the light microscope with a simple stain. In an electron micrograph, ribosomes appear as small spherical dots. Ribosomes often occur in chains termed polysomes.
In an electron micrograph, ribosomes appear as small spherical dots. Ribosomes often occur in chains termed polysomes.
Cell breaking or rupturing is known as cell .
Lysis
_______ is what occurs when a cell breaks or ruptures.
Lysis
Which of the following is a stimulus for endospore formation? Nutrient depletion Exposure to radiation Extreme temperature
Nutrient depletion
Which of the following are types of flagellar arrangements with more than one flagellum? Peritrichous Amphitrichous Monotrichous Lophotrichous
Peritrichous Amphitrichous Lophotrichous
Which of the following are considered external structures of prokaryotic cells? Multiple select question. Pili Nucleoid Granules Flagella
Pili Flagella
Which organelle's small and large subunits are composed of rRNA and protein?
Ribosome
Proteins are synthesized on the_________ , a small spherical structure located in the cytoplasm.
Ribosomes
___________are counterclockwise rotations by flagella that propel a cell forward, whereas________ are clockwise rotations that cause the cell to stop and change its course.
Runs or Run tumbles or tumble
Which of the following represent arrangements of cocci? Sarcina Palisades Streptococci Tetrads
Sarcina Streptococci Tetrads
Which of the following are methods used to identify bacteria? Multiple select question. Serotype Bacterial biochemistry Genetic techniques Form of reproduction Cell morphology
Serotype Bacterial biochemistry Genetic techniques Cell morphology
What are the three most common shapes of bacterial cells? Multiple select question. Irregular Spirillum Coccus Filamentous Bacillus
Spirillum Coccus Bacillus
A _____________is a flexible, spiral-shaped bacterium.
Spirochete
What term represents chains of cocci?
Streptococci
Which two of the following statements about the bacterial S layer are correct? The S layer consists of thousands of copies of a single protein. The S layer is sometimes using in conjugation for DNA transfer. The S layer is rarely observed in cells grown in the lab in rich medium. The S layer is also referred to as the glycocalyx.
The S layer consists of thousands of copies of a single protein. The S layer is rarely observed in cells grown in the lab in rich medium.
Which two of the following statements are correct regarding the bacterial chromosome? The chromosome is coiled around basic proteins to fit inside the cell compartment. The chromosome is coiled around basic proteins to attach to the cell wall. The chromosome carries the genes required for cell maintenance and growth. The chromosome is a long molecule of double-stranded DNA and double-stranded RNA.
The chromosome is coiled around basic proteins to fit inside the cell compartment. The chromosome carries the genes required for cell maintenance and growth.
Archaea are: Multiple select question. able to exist in extreme environments only found in the environment prokaryotic more closely related to Domain Eukarya than to Bacteria the newest life forms
able to exist in extreme environments prokaryotic more closely related to Domain Eukarya than to Bacteria
The________ _________stain technique would be used to discover Mycobacterium tuberculosis in a sputum sample.
acid or Ziehl fast or Neelsen
In a stratified biofilm, (choose two) Multiple select question. anaerobes are found near the bottom aerobes are found near the bottom aerobes are found near the surface anaerobes are found near the surface
anaerobes are found near the bottom aerobes are found near the surface
Plasmids typically carry ______ genes. antibiotic resistance nonessential required essential
antibiotic resistance nonessential
Cells that are related to eukaryotes but similar in structure to bacteria are called ______.
archaea
Cells that are related to eukaryotes but similar in structure to bacteria are called ______. Multiple choice question.
archaea
A(n)________ filament is a periplasmic flagellum found in some spirochete bacteria.
axial
Twisting or flexing of spirochete bacteria is attributed to the
axial filaments
A group of cells in a palisade arrangement will have the cellular morphology
bacillus
The proper term for a rod-shaped bacterial cell is a(n)_________
bacillus
Cylindrical bacterial cells are called _____, whereas spherical bacterial cells are called_____.
bacillus, bacilli, or rods coccus or cocci
Cylindrical bacterial cells are called _____, whereas gently curved cylindrical cells are referred to as________
bacillus, bacilli, or rods vibrio or curviform
The three most common shapes of bacterial cells are known as_______ __________and spirillum/spirochete bacteria. Use technical terms please.
bacillus, bacilli, rods, or rod cocci or coccus
Peptidoglycan is a component of the cell wall in ________.
bacteria
Bacteria and archaea were initially classified based on shape, arrangement, and staining, but were found to have significant differences in _____________ ,and genetics.
biochemistry
The prefix "strepto-" is used to indicate that the cells are arranged in
chains
During ______, bacterial cells move by flagellar motion in response to chemical signals.
chemotaxis
To move towards a chemical attractant by flagellar motion is referred to as positive
chemotaxis
The hereditary material of a bacterial cell is a (normally) single circular strand of DNA known as the bacterial _________-, which is aggregated in the nucleoid.
chromosome
Which two of the following are found in the cytoplasm of a bacterial cell? fimbriae chromosome periplasm ribosomes
chromosome ribosomes
The prefix "staphylo-" is used to indicate that the cells are arranged in:
clusters
The term used for a short, plump bacterial rod is______-
coccobacillus
The bacterial chromosome is coiled around protein molecules for the purpose of
compaction into the cell
Bacterial ________ is the transfer of genetic material between two bacteria cells.
conjugation
The genetic transfer of material through pili is termed ______.
conjugation
Which components of the bacterial endospore are responsible for its resistance to environmental challenges?
cortex coat
The intracellular gelatinous solution is referred to as
cytoplasm
The_______is a network of actin and tubulin filaments that are located just under the cell membrane and that contribute to cell shape.
cytoskeleton
Which of the following are characteristics of a mature endospore? Multiple select question. susceptible to heat susceptible to chemical disinfectants desiccation-resistant radiation-resistant
desiccation-resistant radiation-resistant
The ______________ , scheme of classification, which is restricted to the analysis of bacterial disease agents, divides bacteria first by cell walls and then by shape, arrangement, and physiological characteristics.
diagnostic
Biofilms are often stratified, meaning that Multiple choice question.
different microbes occupy spaces that best fit their environmental needs
The prefix " _________-" means "in pairs."
diplo
he depletion of nutrients is a stimulus for_____ in bacteria.
endospore
True or false: Bacterial endospores are reproductive structures.
false
The process by which an endospore rehydrates and begins cellular metabolism is termed _____.
germination
__________is the process by which an endospore rehydrates and begins cellular metabolism.
germination
Ribosomes make a good target for antibacterial drugs because
human ribosomes have a different structure and would not be susceptible to such drugs.
In bacteria, ribosomes are located ______.
in the cytoplasm
Planktonic bacteria
live as single cells, not in biofilm communities
The peptidoglycan component of the cell wall has _____ sugar chains crosslinked by _____ peptide fragments.
long; short
A tuft of flagella from a single site is referred to as a__________ arrangement, whereas flagella dispersed over the surface of the cell is referred to as
lophotrichous peritrichous
A typical cell of Staphylococcus would be expected to have a diameter of approximately 1
micrometer
A cell wall and some form of glycocalyx are found in ______ bacterial cells.
most
Gram________cells are typically more resistant to drug treatment and chemical control methods than gram-______cells
negative positive
Archaeal cell walls are distinct from bacterial cell walls in that Multiple choice question.
none contain peptidoglycan
A ______________is an extrachromosomal piece of DNA that contains genes not essential for cell growth.
plasmid
Which of the following are found in the cytoplasm of a bacterial cell? Choose two. Multiple select question. pool of amino acids cytoskeleton flagellum lipopolysaccharide
pool of amino acids cytoskeleton
The function of the peptidoglycan in the cell wall is to
prevent the rupture of the cell from internal pressure
Archaeal cell walls are distinct from bacterial cell walls in that some are composed almost entirely of ______. Multiple select question. lipids protein polysaccharides nucleic acids
protein polysaccharides
The site of protein synthesis in the cell, known as the______ , is composed of rRNA and protein.
ribosomes
A bacillus is a _____-shaped bacterial cell.
rod
Counterclockwise rotation of the flagellum causes a bacterial cell to swim or ______ towards a stimulus, interrupted by clockwise rotation in which the cell ______ and changes its course.
run, tumbles
Question Mode Multiple Choice Question A type of glycocalyx called the _______ is loosely attached to the bacterial cell and protects it from dehydration and loss of nutrients. Multiple choice question.
slime layer
A strain is a subgroup of a
species
A coccus is a ______-shaped bacterial cell.
spherical
A subgroup of a species is referred to as a
strain, type, or subspecies
Choose the prefixes that may be used to describe arrangements of bacilli. (Choose two.) vibrio- strepto- staphylo- diplo-
strepto- diplo-
Bacterial endospores are involved in: Multiple choice question.
survival
The origin of the various groupings for cocci, for example strepto-, staphylo-, diplo-, is
the geometry of the cell division planes
The complex external covering composed of two or three layers found on the majority of bacteria is termed the cell
envelope
Fimbriae, flagella, and pili are all examples of _____ structures found in some bacteria.
external
The main function of ______ is sticking to cells and other surfaces.
fimbriae
Appendages that propel bacterial cells through an aqueous environment include axial filaments and __________
flagella or flagellum
The basal body, hook, and filament are components of ___________in bacteria.
flagella or flagellum
The __________is a polysaccharide protective coating outside of the bacterial cell wall that is called either a capsule or slime layer based on its structure.
glycocalyx
The S layer surrounding many bacterial cells is comprised of
protein
The flagellar filament is composed of
protein
Which of the following are components of the peptidoglycan layer of the cell wall? Choose two. protein lipid carbohydrate nucleic acid Correct Answer
protein carbohydrate
Some bacteria are covered with a loose shield called a_________ layer that protects the cell from dehydration and loss of nutrients. Listen to the complete question Need help? Review these concept resources.
slime
A rigid helical bacterial cell twisted twice or more along its axis is described as a(n) ______.
spirillum
The helical structure of a_______is more rigid than the spring-shaped form of a spirochete.
spirillum or spirilla
The prefix _________means "in grape-like clusters." Listen to the complete question
staphylo
The prefix "_____-" means "in a chain".
strepto
Which staining technique allows differentiation of mycobacterial cells?
Acid-fast stain
Which of the following describes the function of fimbriae?
Adhesion
Which is true regarding all bacterial cells? Multiple choice question. All cause disease. All lack a nucleus. All contain a cell wall. All are motile.
All lack a nucleus.
What is the glycocalyx?
An extracellular coating that provides protection to the cell
What bacterial cell type is a flexible, spring-like structure?
Spirochete
A typical cell of Staphylococcus would be expected to have a diameter of approximately
1 μm
Which cell structure is designed to provide shape, support and resistance to osmotic pressure?
Cell wall
Which of the following structures are possessed by all bacterial cells? Multiple select question. Chromosome(s) Cell wall Glycocalyx Cell membrane Ribosomes
Chromosome(s) Cell membrane Ribosomes
Which of these statements indicate ways that the cell envelope contributes to functional differences between bacterial cells? The LPS found in gram-positive cells can cause shock. Reason: LPS is found in gram-negative cells. It is easier to control gram-negative infections. Reason: Actually, their outer membrane makes control more difficult. Different drugs are often required to kill gram-negative cells. Cell wall components can interact with human tissue and cause disease. The outer membrane in gram-negative cells makes them more resistant to control methods. Correct Answer Different drugs are often required to kill gram-negative cells. Cell wall components can interact with human tissue and cause disease. The outer membrane in gram-negative cells makes them more resistant to control methods. Need help? Review these concept resources. Feedback Next Question Reading
Different drugs are often required to kill gram-negative cells. Cell wall components can interact with human tissue and cause disease. The outer membrane in gram-negative cells makes them more resistant to control methods.
What is the purpose of mycolic acid in the mycobacterial cell wall?
It reinforces the cell wall and makes the bacterium resistant to certain chemicals and dyes.
Which of the following makes bacteria and archaea different from eukaryotes? Multiple choice question. They have phospholipids in their cell membrane. They lack a nucleus. They lack chromosomes. They possess a cell wall
They lack a nucleus.
The internal gelatinous matrix of a cell, mostly composed of water, is referred to as _________________
cytoplasm
Another term for the cell membrane (or plasma membrane) is the ____________membrane.
cytoplasmic
The cell membrane may also be referred to as the ______.
cytoplasmic membrane
The basal body of a flagellum is located
embedded within the cytoplasmic membrane, wall, and outer membrane.
The glycan chains of peptidoglycan can be hydrolyzed by the enzyme _____, a host defense naturally found in tears and saliva.
lysozyme
The ability to move is referred to as ______
motility
Motility refers to an organism's ability to ______.
move
The mycobacterial cell wall is reinforced with_________acid
mycolic
If a given bacteria is pink following gram staining that bacteria is gram-_________
negative
Only gram-______ bacteria possess an outer membrane.
negative
Only gram-negative bacteria possess a(n) ______.
outer membrane
The majority of bacteria have a cell envelope. Which component of the cell envelope is found in only some bacterial cells?
outer membrane
The prefix "diplo-" is used to indicate that the cells are arranged in Multiple choice question.
pairs
Bacterial cells have high internal pressure. The________layer of the cell wall provides strength and rigidity to prevent cell lysis.
peptidoglycan
Lysozyme, an enzyme contained in tears and saliva, is a host defense against bacteria. Its substrate is
peptidoglycan
The cell wall in bacteria is primarily composed of
peptidoglycan
During , bacterial cells move by flagellar motion in response to light.
phototaxis
When bacteria move in response to a light source, this overall movement is referred to as ______.
phototaxis
Bacteria that live as single cells are described as
planktonic
A bacteria that appears purple following gram staining is considered gram-_________-
positive
the functions of the cell wall include preventing destruction with changes in osmotic pressure maintaining the shape of the bacterium containing the components for cellular respiration the storage of nutrients
preventing destruction with changes in osmotic pressure maintaining the shape of the bacterium
A curved rod (comma-shaped bacterium) is specifically described as a(n)_______
vibrio
A gently curved bacterium is specifically described as a(n) ______. Multiple choice question.
vibrio