BIOL221 Microbio Exam 2 Prep Part 2
Which of the following are in vivo methods for viral cultivation?
inoculating mice with viruses; inoculating chicken eggs with viruses
Lysogeny is best described as ______.
integration of the viral genome into the host chromosome
Which term refers to the condition in which the bacterial host chromosome carries bacteriophage DNA
lysogeny
Which term refers to the condition in which the bacterial host chromosome carries bacteriophage DNA?
lysogeny
Example: Eukayotic cell that's been exposed to bacteria cells - Eukaryotic cell can engulf the bacteria into the cell, now there's a vesicle that has formed around it - Engulfed vesicle can now associate itself to the lysosome
lysosome is going to destroy it
- generate energy for the cell - composed of a smooth, continuous outer membrane with an inner folded membrane #- produces ATP #- contains cellular strengths of DNA
mitochondria
A ________ virus does not have an envelope surrounding its capsid.
naked
A nonenveloped virus is also called a(n) ______ virus.
naked
An RNA genome that is not in a form ready for translation is called _____ -sense RNA.
negative
Which of the following terms is used to describe a viral RNA genome which CANNOT be immediately translated into protein?
negative-sense
Viruses have a compact and economical structure that is ______.
not cellular
Viruses are considered to be ______ parasites because they multiply by invading a specific host cell and instructing its genetic and metabolic machinery to make and release quantities of new viruses.
obligate intracellular
Viruses that lead to cancer in infected hosts are called ______
oncogenic
What term refers to a virus that can lead to cancer?
oncogenic virus
What is the fate of the cell in a hypotonic environment?
osmotic lysis
A clear area where virus-infected monolayers of cells have been disrupted or destroyed is called a(n) ________
plaque
When observing a monolayer of cells, the areas where virus-infected cells have been destroyed show up as clear, well-defined patches called ______.
plaques
An infectious agent made up of only protein and associated with spongiform encephalopathies is a(n) _______
prion
Which agent is the cause of spongiform encephalopathy?
prion
Besides viruses, two noncellular infectious agents known as _________ and viroids are medically important.
prions
Phage DNA that is latently incorporated into the bacterial host genome is called a ______
prophage
Which of the following is used to describe the phage DNA that is latently incorporated into the bacterial host genome?
prophage
Although the outer shell of viruses is made of ______, viruses lack the machinery to produce those shell components on their own.
protein
Capsomers are composed of _________ (Hint: it is a macromolecule)
protein molecules
All viruses have two parts: a ______ covering and ______ located in a central core.
protein; DNA or RNA
Most host cell receptors that viruses attach to are actually _______ that the cell uses in normal function.
proteins
Do not have cell walls
protozoa and helminths
The virus buds off the membrane and picks up an envelope and spikes during which stage of the viral life cycle?
release
An enzyme capable of taking an RNA genome and generating a DNA copy is called ______.
reverse transcriptase
An enzyme that can synthesize DNA from RNA is called ______.
reverse transcriptase
Distributed throughout the cell: - scattered freely in the cytoplasm and cytoskeleton - attached to the rough endoplasmic reticulum Size and structure: - large and small subunits of ribonucleoprotein - eukaryotic ribosome in 80S, a combination of 60S and 40S subunits
ribosomes
Bacillus/bacilli
rods
Most human viral infections are ______.
self-limiting
Some laboratory animals can propagate viruses in the laboratory more readily than others because many viruses exhibit host ________
specificity
Coccus/cocci
spheres
On this diagram of a naked virus, the arrow indicates a(n) (picture of a single microbe with arrow point to tips sticking out) ________
spike
A disease condition of the brain caused by an infection with prions is called bovine _______ encephalopathy or "mad cow disease".
spongiform
Which of the following diseases are caused by prions?
spongiform encephalopathy
Unlike cellular organisms, viruses are unable to ______.
synthesize their own proteins
A bacteriophage that does not immediately lyse or change the appearance of host cells is called a(n) _______ phage.
temperate
What name is given to a phage "type" which can incorporate itself into the host genome as a lysogenic prophage?
temperate
The category of DNA phages that can participate in a lytic phase or enter into a lysogenic cycle is the ______.
temperate phages
- typical bilayer of phospholipids in which protein molecules are embedded - contain sterols of various kinds - relative rigidity give stability to the membrane - important in cells that do not have a cell wall - cytoplasmic membranes serve as selectively permeable barriers
the cell membrane
Once the virus is inside the cell, the viral nucleic acid is freed by enzymes that break down the viral capsid in a process called ______.
uncoating
Which term describes the process of a virus losing its capsid (and envelope, if it has one) and exposing viral nucleic acids to the immediate environment?
uncoating
Which of the following statements regarding protein synthesis is correct?
All viruses lack the machinery to synthesize proteins. INCORRECT: - Some viruses can synthesize their own proteins - All viruses have protein-synthesizing machinery
agent of anthrax
Bacillus anthracis
Which of the following is considered a monomer (a single unit) of a capsid?
Capsomer
DNA to RNA to protein
Central dogma
In which age group is enterobiasis most prevalent?
Children
Helps with the arrangement of how the genetic information (DNA) is passing the nucleus
Chromatin
Bacteria cells ideally don't have to have a plasmid. They have ...
Chromosome and allows them to live
What is the name given to the protective form of some protozoans?
Cyst
For their genetic material, viruses can contain either ___ or ___ but not both
DNA ; RNA
A theory that attempts to explain the complexity of eukaryotic cells Evidence in support of the theory is the fact that mitochondria that's found in eukaryotic cells #1 : contains ribosomes that is found in bacteria #2 : shape of the mitochondria looks like a rod shaped bacteria similar to chloroplast # all these are found in an eukaryotic cell
Endosymbiotic theory Endo = engulfing symbiosis = relationship
- similar to flagella in structure, but are smaller and more numerous - found only in a single group of protozoa and certain animal cells - used for movement
Eukaryotic cilia
- Thicker and more structurally complex than bacterial flagella - Covered by an extension of the cell membrane - long, sheathed cylinder containing regularly spaced microtubules
Eukaryotic flagella
True or false: The viral envelope and capsid are the same thing.
False
True or false: The interior of eggs normally contains non-pathogenic bacterial cells but no viruses.
False Interior of eggs are normally a sterile environment and free from any type of microbes or viruses
True or false: Antibiotics are an effective treatment for most viral infections.
False antibiotics target bacteria but not viruses
- site of protein modification and shipping - Consists of several flattened, disc-shaped sacs called cisternae - Always closely associated with the endoplasmic reticulum: - Transitional vesicles from the endoplasmic reticulum are picked up at the face of the ----- --------- - Proteins are modified within the cisternae by the addition of polysaccharides and lipids - condensing vesicles pinch-off of the ----- --------- and are then conveyed to lysosomes or transported outside the cell # - PACKAGES THINGS
Golgi Apparatus
Thick peptidoglycan layer
Gram positive
Cells concentration is high
Hypertonic
Leaves a cell in osmosis
Hypertonic (water ALWAYS moves towards a higher solute concentration)
Cells concentration is low
Hypotonic
What is the term which describes a geometric viral form having 20 faces and 12 corners?
Icosahedron
Which term refers to the physical rupture of a cell?
Lysis
Which group includes the roundworms?
Nematode
Without conjugation
No plasmid is shared to make resistance
Surrounds the nucleus
Nuclear envelope Eukayotic
Allows things in and out of the nucleus
Nuclear pore
- inside the nucleus - sites for RNA synthesis - to form something
Nucleolus
Composed of: - endoplasmic reticulum - nuclear envelope - nuclear pore - nucleolus
Nucleus
Movement of water in and out of a cell
Osmosis
Gram negative cells
Outer membrane is at the top thin peptidoglycan layer Inner membrane (also peptidoglycan layer)
No nucleus
Prokaryotic
Which factor enables certain laboratory animals to propagate viruses more readily than others?
Receptor specificity between virus and particular animal hosts
Identify the commonalities between temperate phages and lytic phages.
Release ; Biosynthesis of viral components ; Penetration ; Assembly ; Adsorption
*random info, not really a back and forth thing* plasmids can code for antibiotic resistance gene and can also have a gene that codes for toxins
Result of plasmid - Toxin: hemolysin Toxin will allow you to be able to affect the host *Host can try to engulf and destroy but toxin prevents that from occurring
- closed tubular network without ribosomes - Functions in nutrient processing and in synthesis and storage of nonprotein macromolecules such as lipids #- Missing ribosomes #- Synthesis of lipids
Smooth endoplasmic reticulum (SER)
______ phages enter the prophage state, while ______ phages burst the host cell.
Temperate; lytic
Functions: - anchoring organelles - moving RNA and vesicles - Permitting shape changes and movement
The cytoskeleton
Rough Endoplasmic Reticulum : connects to the Golgi Apparatus : whatever is in vesicle (let's say that it's trying to fuse it outside) : Golgi Apparatus transports that via vesicle : vesicle eventually fuses with the membrane and releases the content outside
Transport process
True or false: In pathogenic helminths, the most developed organs are those of the reproductive system.
True
- Not eukaryotic cells - Not bacterial cell - Collection of non cellular particles
Viruses
What does "obligate" mean in regard to viruses?
Viruses must have a host cell.
A virus capable of infecting a cell would be called ______ while one that cannot carry out infection would be referred to as ______. Multiple choice question.
active; inactive
A virus binds to specific receptor sites on the membrane of a susceptible host cell during the ______ phase of the viral life cycle.
adsorption
Which is NOT an effective strategy for addressing the propagation of viral infections?
antibiotic drugs
Embryonic eggs ______.
are completely sterile
Unlike organisms such as bacteria and protozoa, viruses ______.
are not cellular
During which phase of the viral life cycle are new virions built from their components?
assembly
New virions are built from their components during the phase of the viral life cycle.
assembly
Which of the following describes the various viral "parts" coming together to produce virus particles?
assembly
Antibiotics are effective at combating ______ but not ______.
bacteria; viruses
Any virus that specifically infects bacteria is called a(n) ________
bacteriophage
Which is closest in physical proximity to the nucleic acid of a virus?
capsid
Identify all the components of the nucleocapsid.
capsid and nucleic acid
A protein subunit that forms the viral capsid is called a(n) ________
capsomere
Which of the following is the monomeric unit of a viral capsid?
capsomere
Clostridium botulinum
cause of botulism
Clostridium perfringens
cause of gas gangrene
- cell membrane * cell wall * - chitin - glycoprotein - mixed glycans * cell wall * - glycocalyx
cell walls of fungi
- rigid and provide structural support and shape - different in chemical composition from bacterial and archaeal cell walls - thick inner layer of polysaccharide fibers composed of chitin or cellulose - thin outer layer of mixed glycans
cell walls of fungi
Which group includes tapeworms?
cestodes
strepto
chains
Staphylo
clusters
process of transferring plasmid from one cell to the other Bacteria 1 has plasmids and can share with bacteria 2 that does not have plasmids - sharing of plasmid
conjugation
folds in the inner membrane of the mitochondria are called
cristae
In penetration by ______, the entire virus is engulfed by the cell and enclosed in a vacuole or vesicle.
endocytosis
Which term is used to describe the process in which a virus is engulfed by a cell and enclosed in a vacuole or vesicle?
endocytosis
Naked viruses do not possess a(n) ______________
envelope
Budding is the release of ______ viruses.
enveloped
The sum total of the genetic information carried by a virus is called the viral _________
genome
Which of the following term describes the total nucleic content of a virus?
genome
Which of the host cell structures must usually be specific for adsorption?
glycoprotein receptors
Clostridium tetani
gram positive- rod cause of tetanus
A virus with a rod-shaped capsomer has a(n) ________ capsid, while a virus with a capsid arranged as a multifaceted polygon has a(n) ________ capsid.
helical, icosahedral
A virus with a rod-shaped capsomer has a(n) _____ capsid, while a virus with a capsid arranged as a multifaceted polygon has a(n) _____ capsid.
helical; icosahedral
The limitation of the type of cell that a virus can invade is called the ______ range.
host
Since the hepatitis B virus can only infect liver cells in humans and not in other animals, its ________ ____________ is considered to be highly restrictive.
host; range
Methods to study viruses that use living animals are called _____ methods, whereas methods that use tissue culture are called _____ methods.
in vivo; in vitro
Masses of viruses or damaged organelles of a cell due to a cytopathic effect of viral infection are called _______ bodies.
inclusion
One type of cytopathic effect is the accumulation of ______, compacted masses of viruses or damaged cell organelles within an infected host cell.
inclusion bodies
Which is most important for attachment of a virus to a host cell?
viral specificity for host receptors
An infectious agent that lacks a capsid and merely consists of a strand of RNA is called a(n) ______
viroid
Which of the following is completely composed of RNA?
viroid
The complete set of viruses that are associated with the human body is termed the human __________
virome
Identify the smallest pathogenic agent.
virus
________ are among the smallest infective agents.
viruses
The human virome is the complete set of ______.
viruses that are associated with the human body
Staphylococcus aureus - gram type? - shape? - found?
- gram positive - coccus/spherical - upper respiratory or on a saw??
Microbacterium tuberculosis - gram type? - shape? - found?
- gram postive - rod - TB - Gen Time:12 hours
Gram positive cells
- thick peptidoglycan layer - no OUTER cell membrane/layer; does have a phospholipid bilayer - teichoic acids: arrangements: wall teichoic acids and lipo teichoic acid
Identify all the methods that a virus can use to gain entry into an animal cell.
-Fusion of the viral envelope and the cell membrane.-Engulfment/phagocytosis of the virus.
Which structure immediately encloses viral nucleic acid?
Capsid
Which term is used to describe the phospholipid bilayer found surrounding the capsid of some viruses?
Envelope
2 parts to the nucleus First - found in the nucleoplasm - site for ribosomal RNA synthesis - collection area for ribosomal subunits Second - made of linear DNA and histone proteins - genetic material of the cell
Nucleolus Chromatin
- allows transport materials from the nucleus to the cytoplasm and to the cell's exterior - ribosomes attached to its membrane surface - protein synthesis - connects to the Golgi Apparatus
Rough endoplasmic reticulum (RER)
Which disease is characterized by brain tissue pathology due to prions?
Spongiform encephalopathy
- outermost layer that comes into direct contact with the environment - composed of polysaccharides - Appears as: - a network of fibers - a slime layer - a capsule - Contributes to protection, adherence, and signal reception
The Glycocalyx
Teichoic acid gives ...
The surface of a Gram positive organism a negative charge
The viral process of attaching to the host cell receptor for the virus is called ________
adsorption
Which is the correct term to describe viral adherence to a host cell receptor?
adsorption
Which viral stage occurs first?
adsorption
Mature virus particles are constructed from nucleic acid and protein during the ______ phase of the viral life cycle.
assembly
New virions are built from their components during the ______ phase of the viral life cycle.
assembly
New virions are built from their components during the _________ phase of the viral life cycle.
assembly
What term is used to specifically describe the types of viruses that infect bacteria?
bacteriophage
Each viral capsid is constructed from identical subunits called ______.
capsomeres
- found in algae and plant cells - capable of converting energy from sunlight into chemical energy through photosynthesis - produce oxygen gas as a by-product of photosynthesis - resemble mitochondria but are larger, contain special pigments, and are more varied in shape
chloroplasts
Viral DNA polymerase genes are expressed during the _____ stage of the synthesis phase of the viral life cycle.
early
The 2 principal processes by which viruses penetrate host cells are ________ (engulfment) and direct fusion.
endocytosis
A virus that has a membranous layer external to the nucleocapsid is called a(n) __________ virus
enveloped
When a bacterium acquires a new trait from its temperate phage, it is called _____.
lysogenic conversion
Together, the capsid and nucleic acid of a virus are called the _____________
nucleocapsid
- most prominent organelle of eukaryotic cells - separated from the cell cytoplasm by an external boundary called the nuclear envelope - perforated with small, regularly spaced pores, formed at sites where the membranes unite - macromolecules migrate through the pores to the cytoplasm and vice versa
nucleus
Viruses have tropisms, that is they can infect ______.
only cells of a certain tissue type
Infections in which cells harbor the virus but are not immediately lysed are called _______ infections.
persistent
_______ infections, when the cell harbors a virus and is not immediately lysed, can last from a few weeks to the remainder of the host's life.
persistent
Which of the following describes the "clear" area where a virus-infected cell lysed and infected all the neighboring cells and lysed those too?
plaque
- Extra chromosomal (extra piece of DNA in bacteria chromosome) - Codes for genes; antibiotic resistant; needed for survival - non essential (the cell can survive without it) - not all bacteria cells have a plasmid
plasmid
Some diseases of the nervous system result from an infectious agent in the form of protein fibrils that is called a ______.
prion
Viruses typically attach to what type of host membrane receptors?
proteins
Which macromolecule composes capsomeres?
proteins
The virus buds off the membrane and picks up an envelope and spikes in the _______ stage of the viral life cycle.
release
True or false: Most viral infections do not result in death of the host organism.
true
Plants are parasitized by virus-like agents composed of only naked strands of RNA that are called ________
viroids
A type of virus that parasitizes other viruses infecting the same host cell is called a(n) ______
virophage
What is the term for a type of virus that parasitizes other viruses infecting the same host cell?
virophage
Which of the following is true regarding viruses?
viruses are not cellular -answers made to be true: - Viruses are not single-celled - Viral structure is very unlike that of any cell
What is the motile feeding stage of protozoa called?
trophozoites
Viruses that can infect only certain tissues are described as having a tissue specificity or _____.
tropism
Vesicles: * - contain a variety of enzymes involved in the intracellular digestion of feed particles and protection against invading microorganisms - participate in the removal of cell debris in damaged tissue #helps digest things or to give up things that the cell does not want * - membrane-bound sacs containing fluids or solid particles to be digested, excreted, or stored - found in phagocytic cells in response to food and other substances that have been engulfed - Contents of a food vacuole are digested through a merger of a vacuole with a lysome #may contain things that the cell wants to get rid of; merges with a lysome
- Lysosomes - Vacuoles
What could be the result of the presence of a plasmid in a bacteria cell?
- acquisition of antibiotic resistant gene - plasmid can code for toxins so bacteria can produce a toxin and the toxin it produce can be a result of acquired plasmid from another bacteria the codes for that toxin - making the recipient bacteria more pathogenic
Three types of cytoskeletal elements: - long, thin protein strands - ropelike structures - long, hollow tubes
- actin filaments - intermediate filaments - microtubules
3 things plasmids can code for ...
- antibiotic resistance genes - toxins - enzymes
Helicobacter pylori - gram type? - shape? - found?
- gram negative - ??? - gastric ulcers
E. coli - gram type? - shape? - found?
- gram negative - rod - colon - Gen time: 30 mins
Klebsiella pneumoniae - gram type? - shape? - found?
- gram negative - rod - lactose fermented McConkey agar
Steptococcus pneumoniae - gram type? - shape? - found?
- gram positive - cocci/spherical - alpha hemolytic
Streptococcus pyogenes - gram type? - shape? - found?
- gram positive - cocci/spherical - beta hemolytic
Staphylococcus Epidermis - gram type? - shape? - found?
- gram positive - coccus/spherical - skin
Microbacterium leprae - gram type? - shape? - found?
- gram positive - rod - ???
Identify the virus types which are released from host cells by lysis.
1. complex 2. naked
List the correct order of viral life cycle phases, starting with the first at the top.
1.adsorption 2.penetration/uncoating 3.synthesis 4.assembly 5.release
The microorganism with a mucoid colonial morphology as a result of the presence of a slime layer is
Klebsiella pneumoniae
Plasmid can code for anti-biotic resistant gene ex. beta-lactamase (needed for bacteria cells to respond to penicillin)
Without plasmid, cannot provide anti-biotic resistance
Is it possible for a bacterial cell infected with a temperate phage to replicate?
Yes
The term "naked" used in describing viruses implies: the lack of ______.
a lipid envelope
Clostridium difficile (C. diff)
a serious gastrointestinal disease
Viruses are best described as ______ rather than alive.
active
During the release stage of the viral multiplication cycle, enveloped viruses leave their host cells through ________, or exocytosis.
budding
Two ways in which newly assembled viruses are released from host cells are through ______ or exocytosis by enveloped viruses, and through ________ (rupture) by naked viruses.
budding; lysis
At minimum, viruses are composed of nucleic acid and a _________ comprised of protein.
capsid
The structure directly surrounding the viral nucleic acid is the _________, a coat of proteins.
capsid
If bacteria cell is encapsulated
it would not be able to be engulfed because of the anti phagocytic property
Viral capsid proteins are synthesized during the _____ stage of the synthesis phase of the viral life cycle.
late
After assembly of nucleic acids and proteins into hundreds of bacteriophages, the host cell ______ and releases the mature virions.
lyses
Both naked and complex viruses are released from host cells via ________
lysis
A bacterium acquires a new trait from its temperate phage through a process called _______ _______
lysogenic conversion
A noncellular infectious agent that depends on other viruses for replication is known as a(n) ________ virus.
satellite
A virus-like particle that is dependent on other viruses for replication is called a ______.
satellite virus
What term is used to describe a virus type which depends on other viruses for replication?
satellite virus
Viruses are classified based on genetic makeup, chemical composition, and ______.
structure
What are the three main criteria used to classify viruses?
structure, genetic makeup, and chemical composition