Microbiology Exam 2
The best definition of endosymbiosis is ________.
a pre-eukaryotic cell was infected by a prokaryote, and symbiosis between the two cell types gave rise to the modern-day eukaryotic cell
The _____ stain is used to stain and differentiate Mycobacterium and Nocardia from other bacteria.
acid-fast
Protists include ________.
algae and protozoa
Virus capsids are made from subunits called _____.
capsomeres
Bacterial cells could have any of the following appendages except _____.
cilia
Eukaryotic flagella differ from bacterial flagella because only eukaryotic flagella ________.
contain microtubules
Fungi that grow as yeast at one temperature but will grow as mold at another temperature are called _____.
dimorphic
Mitochondria possess all of the following except ________.
enzymes for photosynthesis
A specific animal virus has the ability to attach to and enter almost any animal host cell.
false
All fungi cause some kind of disease in plants and animals.
false
All fungi have hyphae.
false
Chitin is a chemical component of the cell walls of _____.
fungi
Lipopolysaccharide is an important cell envelope component of _____________.
gram-negative bacteria
Larvae and eggs are developmental forms of _____.
helminths
Which of the following describes the relationship between the fungal hyphae and mycelia?
hyphae are filamentous cells that grow together in an intertwined mass called a mycelium
Protozoan endoplasm contains _____.
mitochondria
Mammalian viruses capable of starting tumors are _____.
oncoviruses
The term that refers to the presence of flagella over the cell surface is _____.
peritrichous
The RN explains the pinworm life cycle to the student's mother. Which of the following statements by the mother demonstrates a need for further education and reinforcement of the nurse's teaching?
pinworm is transmitted through droplets in the air
Visible, clear, well-defined patches in a monolayer of virus-infected cells in a culture are called _____.
plaques
Which of the following is mismatched?
plasmids - genes essential for growth and metabolism
The most immediate result of destruction of a cell's ribosomes would be ________.
protein synthesis would stop
Cell walls are not usually found in _____.
protozoa
What type of phage enters an inactive prophage stage?
temperate
Eukaryotic flagella differ from prokaryotic flagella in that ________.
they are thicker, they are covered by membrane and they contain microtubules
Fungi can reproduce both sexually and asexually.
true
Larval development of helminths occurs in which host?
Intermediate (secondary) host
The cytoskeleton ________.
all of the choices are correct
The eukaryote cell membrane is composed of _____.
all of the choices are correct
Which of the following is a type of cytopathic effect?
all of the choices are correct
Which of the following is found in eukaryotic cells but not in the cells of bacteria?
all of the choices are correct
Which of the following will not support viral cultivation?
all of the choices will support viral cultivation
The group of protozoa that have gliding motility are the _____.
apicomplexa/sporozoa
Gram-negative bacteria
are less susceptible to antibiotics that target peptidoglycan than gram-positive organisms.
Plasmids ________.
are often the site of pathogenic genes
The two functions of bacterial appendages are ________.
attachment and motility
Viruses that infect bacteria are specifically called _____.
bacteriophages
A flagellum is anchored into the bacterial cell envelope by its _____.
basal body
A(n) _______ is the protein shell around the nucleic acid core of a virus.
capsid
Which structure protects bacteria from being phagocytized by white blood cells?
capsule
A common method for cultivating viruses in the lab is to use in vitro systems called _____ cultures.
cell
The site(s) for most ATP synthesis in bacterial cells is(are) the _____.
cell membrane
All of the following are found in some or all protozoa except ________.
cell wall
Which organelle is found in algae but not found in protozoa or fungi?
chloroplast
When a eukaryotic cell is not undergoing mitosis, the DNA and its associated proteins appear as a visible network of dark fibers called the _____.
chromatin
Viral genetic studies, vaccine development and clinical identification would not be possible without the ability to________.
culture viruses in vivo andin vitro
Which of the following is not a characteristic of a transformed cell?
decreased growth rate
Adulthood and mating of helminths occur in which host?
definitive host
Satellite viruses are ________.
dependent on other viruses for replication
Most helminths are macroscopic, yet they are studied in the field of microbiology. This classification is due to the fact that during their lifecycle, they may produce which microscopic structures?
eggs or larvae
Boiling water (100°C) can normally destroy endospores.
false
Both gram-positive and gram-negative cells have outer membranes.
false
Each bacterial species represents a distinct organism that can produce viable offspring when mating with other bacteria of its kind.
false
Glycoprotein spikes are essential for mediating the release stage of the viral life cycle.
false
Gram-negative bacteria do not have peptidoglycan in their cell walls.
false
Scientists believe that the modern eukaryotic cell evolved 3.5 billion years ago when a photosynthetic bacteria and an aerobic bacteria fused together.
false
The adeno-associated virus (AAV) is a prion.
false
The cell wall of fungi and algae are chemically identical to the bacterial cell wall.
false
The gram-positive cell wall is considered stronger than that of gram-negative cells since its hydrophobic outer membrane contains an endotoxin.
false
The nuclear envelope is a single layer.
false
The slime layer provides bacteria greater pathogenicity as compared to the capsule.
false
The term diplococcus refers to an irregular cluster of spherical bacterial cells.
false
Viruses are ultramicroscopic because they range in size from 2 mm to 450 mm.
false
Amoebiasis (amoebic dysentery) is most commonly contracted through the ________.
fecal-oral route from contaminated food or water
During the Gram stain, _____ cells decolorize when the alcohol is applied.
gram-negative
Which of the following is not true of the outer membrane?
gram-positive bacteria have an outer membrane
Lysozyme is most effective against _____.
gram-positive organisms
The difference in cell wall structure of Mycobacterium and Nocardia compared to the typical gram-positive bacterial cell wall structure is that they ________.
have a predominance of unique, waxy lipids
Which of the following are mismatched?
heterotroph - synthesize organic nutrients using light energy and CO2
Viruses attach to their hosts via ________.
host glycoproteins
Which of the following does not pertain to helminths?
in kingdom protista
All of the following structures contribute to the ability of pathogenic bacteria to cause disease except the _____.
inclusions
The activation of a prophage is called _____.
induction
T-even phages ________.
infect Escherichia coli cells
The bacterial chromosome ________.
is part of the nucleoid
Which of the following does not pertain to endotoxin?
it is found in acid-fast bacterial cell walls
Viruses that cause infection resulting in alternating periods of activity with symptoms and inactivity without symptoms are called _____.
latent
When a bacterium acquires a trait from its temperate phage, it is called _____.
lysogenic conversion
The group of protozoa that have flagella are the _____.
mastigophora
Viruses have all the following except ________.
metabolism
There are nine peripheral pairs and one central pair of _______ found inside eukaryotic flagella and cilia.
microtubules
Which fiber of the cytoskeleton is a hollow tube that is also a component of flagella and the spindle fibers that form during mitosis?
microtubules
Which organelle contains cristae where enzymes and electron carriers for aerobic respiration are found?
mitochondria
Filamentous fungi are called _____.
molds
Cells grown in culture form a(n) _____.
monolayer
The eukaryotic cell's glycocalyx is ________.
mostly polysaccharide
Chemotaxis refers to the ability to ________.
move in response to a chemical
The woven, intertwining mass of hyphae that makes up the body of a mold is a _____.
mycelium
The site for ribosomal RNA synthesis is the _____.
nucleolus
All bacterial cells have ________.
one or more chromosomes
The laboratory report shows that a motility test was performed on the sample with positive results.Thinking about bacterial movement, the RN is aware that this bacterium could possess which structure(s) for motility?
one or more flagella
Infectious protein particles are called _____.
prions
Two noncellular agents, smaller than viruses, are the infectious proteins called _______ and the infectious RNA strands called ________.
prions; viroids
Cilia are structures for motility found primarily in _____.
protozoa
Viral spikes ________.
protrude from the envelope
The chemical components of ribosomes are proteins and _____.
rRNA
Viruses acquire envelopes around their nucleocapsids during _____.
release
The group of protozoa that use pseudopodia to move are the _____.
sarcodina
The transfer of genes during bacterial conjugation involves rigid, tubular appendages called _____.
sex pili
What structures are used by bacteriophages to attach to host cell receptors?
tail fibers
The first primitive eukaryotic cells likely evolved from _____.
the last common ancestor
What is the rationale for providing intravenous fluids and oxygen support for this patient?
these measures are supportive therapies while the disease runs its course
The motile, feeding stage of protozoa is called the _____.
trophozoite
Alcohol-based compounds can weaken the outer membrane.
true
All algae have chloroplasts.
true
Archaea do not have the typical peptidoglycan structure found in bacterial cell walls.
true
Bacteria in the genus Mycoplasma and bacteria called L-forms lack cell walls.
true
Endospores of certain bacterial species can enter tissues in the human body, germinate, and cause an infectious disease.
true
Eukaryotic mitochondria have their own 70S ribosomes and circular DNA.
true
Infections caused by fungi are called mycoses.
true
Pili used for conjugation are only found on gram-negative bacteria.
true
Prophages can be activated into viral replication and enter the lytic cycle.
true
Rough endoplasmic reticulum is studded with ribosomes.
true
Some bacteria have a cytoskeleton of protein polymers to help maintain their shape.
true
The Last Common Ancestor gave rise to the cells in the following three domains we recognize today: the Bacteria, the Archaea, and the Eukarya.
true
The bacterial cell membrane is a site for many enzymes and metabolic reactions.
true
The cell envelope of gram-positive bacteria has two layers: a thick cell wall and the cell membrane.
true
The cell envelope or its parts can interact with human tissue and cause disease.
true
Viral spikes are inserted into the host cell membrane before budding or exocytosis.
true
Viruses are simple, noncellular, and lack ribosomes.
true
Viruses are unable to multiply outside of a host cell.
true
When a virus enters a host cell, the viral genes redirect the genetic and metabolic activities of the host cell.
true
All of the following are helminths except _____.
trypanosomes
Host range is limited by________.
type of host cell receptors on cell membrane
The process of dissolving the envelope and capsid to release the viral nucleic acid is _____.
uncoating
Protists with contractile vacuoles ________.
use them to expel excess water from the cell
Lysogeny refers to ________.
viral genome inserting into bacterial host chromosome
Infectious naked strands of RNA that affect plants are called _____.
viroids
The development of antiviral drug therapy is difficult because ________.
viruses are obligate intracellular parasites so the host cell can be harmed by the drug
Creutzfeldt-Jacob disease is ________.
a spongiform encephalopathy of humans