Microbiology Exam 1
Lipopolysaccharide is an important cell wall component of
Gram-negative bacteria
A prokaryotic cell wall that is primarily composed of peptidoglycan with small amounts of teichoic acid and lipoteichoic acid is
Gram-positive
Which of the following has historically been the first division in a system of bacterial taxonomy?
Gram-positive vs gram-negative cells
The stacks of thylakoids in a chloroplast are called
Grana
The most common infectious cause of death worldwide is
HIV/AIDS
Larvae and eggs are developmental forms of
Helminths
When a virus is noninfectious it is termed __________.
Inactive
All of the following structures contribute to the ability of pathogenic bacteria to cause disease, except
Inclusions
A bacterial cell that exhibits a single group of flagella is called
Lophotrichous
Bacteria with small bunches of flagella emerging from the same site are said to be
Lophotrichous
The eukaryotic cell's glycocalyx is
Mostly polysaccharide
A bacterial genus that has waxy mycolic acid in the cell walls is
Mycobacterium
Viruses that consist of only a nucleocapsid are considered
Naked viruses
A taxonomical outline of bacterial species based on shared evolutionary histories would be described as a
Phylogenetic system
Which is mismatched?
Plasmids-genes essential for growth and metabolism
Which of the following is the cause of malaria?
Plasmodium
Which of these structures are used by bacteriophages to attach to the host cell wall?
Tail fibers
Which term is not used to describe bacterial cell shapes?
Tetrad
The primary function of the cell membrane is
To regulate the transport of molecules in and out of the cell.
The motile feeding stage of protozoa is called the
Trophozoite
All of the following are helminths except (pinworms, flukes, trypanosomes, roundworms, and tapeworms)
Typanosomes
Host range is limited by the
Type of host cell receptors on cell membrane
Which of the following, pertaining to prokaryotic cell membranes, is mismatched?
Unique hydrocarbon present- cyanobacteria
Protists with contractile vacuoles
Use them to expel excess water from the cells
Infectious naked strands of RNA that parasitize plants are called
Viroids
Which of the three domains includes organisms that would be most likely to survive the environmental conditions that existed on Earth nearly 4 billion years ago?
Archaea
According to current thought regarding the domains of life, which two domains are believed to be the most closely related?
Archaea and Eukarya
All of the following pertain to endotoxins, except they
Are found in acid-fast bacterial cell walls
All of the following pertain to virus envelopes except they
Are located between the capsid and nucleic acid
All microorganisms are best defined as organisms that
Are too small to be seen with the unaided eye
Fungal Spores
Are used to identify fungi
Which of the following is a scientific name?
Bacillus subtilis
Which of the following lists the correct descending taxonomic hierarchy (left to right)?
Family, Genus, Species
In eukaryotic cells, the structure primarily responsible for the adherence of cells to surfaces in the environment and the formation of biofilms is the
Glycocalyx
Which organelle is a stack of flattened, membranous sacs that functions to receive, modify, and package proteins for cell secretion?
Golgi apparatus
Which structure or molecule is not found in the cell nucleus?
Golgi apparatus
The smooth endoplasmic reticulum functions in synthesis of
Lipids
Which of the following are not considered microorganisms?
Mosquitoes
What would be the power of magnification when using a microscope with a 10x ocular lens and a 45x objective lens?
450x
All bacterial cells have
A chromosome
Where are you most likely to find prokaryotes belonging to the domain Archaea?
A hot spring
An isolated colony is formed when
A single cell divides many times to a mound of identical cells
Creutzfeldt-Jakob disease is
A spongiform encephalopathy of humans
The nurse in an emergency department is reviewing discharge instructions with a client. The client asks for clarification of a zoonosis, in regards to the type of illness. What is the best response by the nurse?
A zoonosis is a disease typically found in animals, but which infects humans.
The best understood bacterial cytoskeletons are composed primarily of
Actin
Bacteriophage go through similar stages as animal viruses except
Adsorption
The correct sequence of events in viral multiplication is
Adsorption, penetration, replication, assembly, maturation, release
Protists include
Algae and protozoa
In which of the following conditions is/are microbial infection often implicated as a cause?
All of the choices are correct
The cytoskeleton
All of the choices are correct
Endospores are
All of these choices are correct
Host cells of viruses include
All of these choices are correct
Uncoating of viral nucleic acid
All of these choices are correct
Viral cultivation is used for
All of these choices are correct
Viruses have the ability to infect the following cell types.
All of these choices are correct
Which of the following is a type of cytopathic effect?
All of these choices are correct
Which of the following is found in eukaryotic cells but not in prokaryotic cells?
All of these choices are correct
Organisms called parasites are
Always harmful to their hosts
Which is incorrect about prophages?
Always lyse the host cells
The periplasmic space is
An important reaction site for substances entering and leaving the cell
When microbes are introduced into the environment to restore stability, the process is called
Bioremediation
Which of the following will not support viral cultivation?
Blood agar cultures
The viral _____ is responsible for introducing the viral DNA or RNA into the cell.
Both capsid and envelope
The most widely used type of light microscope is the
Bright-field microscope
How do enveloped animal viruses exit their host?
Budding or exocytosis
The bacterial flagellum moves
By rotation that is powered by the proton motive force
Helical and icosahedral are terms used to describe the shapes of a virus
Capsid
Viral capsids are made from subunits called
Capsomers
Which structure protects bacteria from being phagocytized?
Capsule
The scientist(s) that proposed assigning organisms to one of three domains is/are
Carl Woese and George Fox
All of the following are found in some or all protozoa except
Cell Walls
If bacteria living in salty seawater were displaced to a freshwater environment, the cell structure that would prevent the cells from rupturing is the
Cell wall
The outcome of the Gram stain is based on differences in the bacterial cell's
Cell wall
Peptidoglycan is a unique macromolecule that composes the bacterial
Cell walls
Bacteria and Archaea can be differentiated from one another by the
Chemical makeup of the cell wall
Organelles found in algae but not found in protozoa or fungi are the
Chloroplasts
Bacterial cells could have any of the following appendages, except
Cilia
When a rod-shaped bacteria is short and plump, it is called a
Coccobacillus
Magnetosomes are
Composed of magnetic iron oxide particles
Eukaryotic flagella differ from prokaryotic flagella. Only eukaryotic flagella
Contain microtubules
The virus-induced, specific damage to the host cell that can be seen in a light microscope is called
Cytopathic effect
Excess nutrients that the cell may store for later use may be found within
Cytoplasmic granules
Satellite viruses are
Dependent on other viruses for replication
Fungi that grow as yeast at one temperature but will grow as mold at another temperature are called
Dimorphic
The genetic core of every virus particle always contains
Either DNA or RNA
The cell's series of tunnel-like membranes functioning in transport and storage are the
Endoplasmic reticulum
Chemical analysis of a bacterial cell structure detects calcium dipicolinic acid. What is the identity of this structure?
Endospore
Which of the following is not associated with every virus?
Envelope
Which of the following parts of a virus is/are not always present?
Envelope
The three basic groups of viruses based on morphology include
Enveloped viruses, non enveloped viruses, and complex viruses
The short, numerous bristlelike appendages used by some bacterial cells for adhering to surfaces are called
Fimbriae
Please select the statement which is incorrect regarding fixed preparations.
Fixed preparations are used to view live cells
A bacterial cell exhibiting chemotaxis probably has
Flagella
Chitin is a chemical component of the cell walls of
Fungi
Which is not a characteristic of fungi?
Fungi are photosynthetic
Nutrient agar is a microbiological growth medium designed to grow a wide variety of bacterial species. The medium contains beef extract, a mix of naturally occuring proteins, sodium chloride, and 1.5% agar. This medium is classified as a
General purpose, complex, solid medium
Encouraging the growth of a microbe by altering the temperature, along with the concentration of gases like oxygen or carbon dioxide, is best referred to as
Incubation
Microorganisms called psychrophiles will grow only at low temperatures (at or near 0°C). This restriction on a microbes growth would most directly impact
Incubation
The event that occurs in bacteriophage multiplication that does not occur in animal virus replication is
Injection of the viral nucleic acid into the host cell
In the human _______ Escherichia coli begins to colonize while establishing infestation.
Intestines
The bacterial chromosome
Is part of the nucleoid
All of the following are correct about a slime layer, except
It enables movement of cells
Viruses that cause infection resulting in alternating periods of activity with symptoms and inactivity without symptoms are called
Latent
The organelle involved in intracellular digestion of food particles is the
Lysosome
The ability to make objects appear larger in order to view them is known as __________ while being able to see detail and distinguish between two separate objects is known as __________.
Magnification; resolution
Other than maintaining the shape of the cell, what is the primary function of the cell wall, and which component contributes most to this function?
Maintaining strength; peptidoglycan
Which of the following diseases is transmitted by mosquitoes?
Malaria
If a patient cultures show positive results for Haemophilus influenzae, then you know ______ is present.
Meningitis
All of the following are characteristics of viruses except
Metabolism
Please choose the statement which best explains the significance of microorganisms not being culturable.
Microbes that cannot be cultured may be the cause of diseases which are now considered noninfectious
What unit of measure is most appropriate for expressing the size of bacteria?
Micrometer
The eukaryotic organelle that most resembles a bacterial cell is the
Mitochondria
Which organelle contains cristae where enzymes and electron carriers for aerobic respiration are found?
Mitochondria
Filamentous fungi are called
Molds
Which kingdom does not contain any eukaryotes?
Monera
Which body system is mainly affected by Creutzfeldt-Jakob disease?
Nervous system
An important indicator of evolutionary history is the
Nitrogen base sequence of rRNA
Which type of virus is most likely to cause cell lysis and rupturing of an infected animal cell when it is released?
Non enveloped virus
The site for ribosomal RNA synthesis in eukaryotes is the
Nucleolus
Viruses cannot multiply unless it invades a host cell; therefore, they are considered
Obligate intracellular parasites
Of the photosynthetic bacteria, cyanobacteria produce __________ as a product of photosynthesis, but the green and purple sulfur bacteria do not produce this substance.
Oxygen
Disease-causing microorganisms are called
Pathogens
The molecule primarily responsible for the strength and stability of the bacterial cell wall is
Peptidoglycan
The term that refers to the presence of flagella all over the cell surface is
Peritrichous
The ability of cell shape that varies extremely is called
Pleomorphism
A __________ stain is one where the dye adheres to the cell whereas a __________ stain is one that colors the background surrounding the cell, leaving the cell unstained.
Positive; negative
Noncellular infectious protein particles are called
Prions
The function of bacterial endospores is
Protection of genetic material during harsh conditions
The most immediate result of destruction of a cell's ribosomes would be
Protein synthesis would stop
The cell membrane is composed of __________
Proteins dispersed throughout a phospholipid bilayer
In Whittaker's system, the protozoa and algae are classified in the kingdom
Protista
Cell walls are not found on typical cells of
Protozoa
Cilia are found in certain
Protozoa
When buds remain attached, they form a chain of yeast cells called
Pseudohyphae
In a light microscope, the objective lens forms the __________ image, which then is magnified by the ocular lens to form the __________ image that is received by the eye.
Real; virtual
Viruses acquire envelopes around their nucleocapsids during
Release
Which of the following represents size relationships from smallest to largest?
Rhinovirus, Ebola virus, Staphylococcus cell, yeast cell, red blood cell, squamous epithelial cell
Choose the answer that best completes this statement's blanks in the correct order. When all the flagella on a cell rotate in a counterclockwise fashion, the cell is propelled forward in a movement known as a __________, but when the flagella reverse direction, the cell stops and changes course in an action known as a __________.
Run; tumble
To obtain a three-dimensional view of the surface of a protozoan parasite with a total magnification of 10,000x, the best instrument to use would be a
Scanning electron microscope
The transfer of genes during bacterial conjugation involves rigid, tubular appendages called
Sex Pili
The smallest taxon is
Species
In bacteria such as members of the Bacillus and Clostridium genera, nutrient depletion is likely to result in
Sporulation
The process of endospore formation is _____________, while the process of an endospore growing into a vegetative cell is ____________.
Sporulation; germination
Bacterial endospores are not produced by
Staphylococcus
An isolation technique in which an inoculating loop is used to spread a liquid sample over the surface of a solid medium, following a pattern that gradually thins out the sample is a
Streak plate method
Ribosomes function primarily to
Synthesize proteins
Which of the following makes possible the differentiation of members of the genus Mycobacterium and the genus Nocardia from other bacteria?
The acid-fast stain
The nucleocapsid is composed of
The nucleic acid along with the capsid
The difference in cell wall structure of Mycobacterium and Nocardia compared to the typical gram-positive bacterial cell wall structure is
The predominance of unique, waxy lipids
The descriptive groupings of virus into categories such as icosahedral and helical are based on
The shape of the nucleocapsid
When a virus enters a lysogenic phase, it means
The virus is integrated into the DNA of the host cell and is latent
Which of the following explains why archaeons are extremophiles?
They are ancient, primitive organisms that adapt well to extreme conditions because they have retained characteristics of the cells that first evolved when Earth's conditions were far more extreme.
Which statement is not a characteristic of biofilms?
They involve bacteria only