CH13: Viruses, Viroids, and Prions
Viruses A. are obligatory intracellular parasites B. contain a lipid coat that surrounds the nucleic acid C. can only function inside a host cell D. A and B E. A and D F all of the above
A and D they contain a protein coat that surrounds the nucleic acid
Protein sub-units that make up the protein coat that protects the nucleic acid A. Caspid B. Capsomeres C. Envelope D. Spikes
Capsomeres
The protein coat that protects the nucleic acid A. Caspid B. Capsomeres C. Envelope D. Spikes
Caspid
Bacteriophages are this type of virus A. Helical Viruses B. Polyhedral Viruses C. Enveloped Viruses D. Complex Viruses
Complex Viruses
Have complicated structures A. Helical Viruses B. Polyhedral Viruses C. Enveloped Viruses D. Complex Viruses
Complex Viruses
Cell infection by a virus causes observable changes to the cells called cytopathic effects A. cultivated in a living animal B. Cultivated in cell culture C. Cultivated in embryonated poultry eggs
Cultivated in cell culture
Useful for studying viral behavior but also for clinical diagnostic purpose A. cultivated in a living animal B. Cultivated in cell culture C. Cultivated in embryonated poultry eggs
Cultivated in cell culture
How vaccines are produced A. cultivated in a living animal B. Cultivated in cell culture C. Cultivated in embryonated poultry eggs
Cultivated in embryonated poultry eggs
Viruses possess genetic material comprised of ________. A. DNA or RNA B. DNA only C. RNA only D. protein only E. DNA and RNA together
DNA or RNA
Derived for human embryos, widely used for culturing viruses that require a human host A. Cytopathic Effect B. Primary cell lines C. Diploid cell lines
Diploid cell lines
A combination of lipids, proteins, and carbs that cover the protein coat that protects the nucleic acid A. Caspid B. Capsomeres C. Envelope D. Spikes
Envelope
Herpes Simplex virus is this type of virus: A. Helical Viruses B. Polyhedral Viruses C. Enveloped Viruses D. Complex Viruses
Enveloped Viruses
Influenza is this type of virus A. Helical Viruses B. Polyhedral Viruses C. Enveloped Viruses D. Complex Viruses
Enveloped Viruses
Roughly spherical shaped viruses A. Helical Viruses B. Polyhedral Viruses C. Enveloped Viruses D. Complex Viruses
Enveloped Viruses
True or False Ebola virus is one of the smallest viruses that infect humans
False
True or False Viruses can be grown only in living animal or plant hosts
False
True or False Capsomeres make up the spikes on the surfaces of viruses to aid in attachment to the host cell.
False
True or False Some viruses are able to multiply independently outside a host cell.
False
True or False Viruses that contain RNA are called virions and those with DNA are called viroids.
False
True/False Nucleic Acid can only be single-stranded
False Nucleic acid can be single-stranded or double-stranded
True/False A virus can have both DNA and RNA
False Viruses can have DNA or RNA but NEVER both
Rabies and Ebola hemorrhagic fever are this type of virus A. Helical Viruses B. Polyhedral Viruses C. Enveloped Viruses D. Complex Viruses
Helical Viruses
Resemble long rods that may be rigid or flexible A. Helical Viruses B. Polyhedral Viruses C. Enveloped Viruses D. Complex Viruses
Helical Viruses
A virus that has 20 triangular surfaces and 12 corners A. Helical Viruses B. Polyhedral Viruses C. Enveloped Viruses D. Complex Viruses
Polyhedral Viruses
A virus that has many many sides A. Helical Viruses B. Polyhedral Viruses C. Enveloped Viruses D. Complex Viruses
Polyhedral Viruses
The caspid is in the shape os a icosahedron A. Helical Viruses B. Polyhedral Viruses C. Enveloped Viruses D. Complex Viruses
Polyhedral Viruses
The poliovirus is this type of virus A. Helical Viruses B. Polyhedral Viruses C. Enveloped Viruses D. Complex Viruses
Polyhedral Viruses
Derived from tissue slices, tend to die after only a few generations A. Cytopathic Effect B. Primary cell lines C. Diploid cell lines
Primary cell lines
A way that some cells attach to host cells A. Viriods B. Capsomeres C. Cytopathic Effect D. Spikes
Spikes
Can be used as a means of identification A. Viriods B. Capsomeres C. Cytopathic Effect D. Spikes
Spikes
Cardohydrate-protein complexes that project from the surface of some viruses A. Caspid B. Capsomeres C. Envelope D. Spikes
Spikes
A system that groups viruses into families based on nucleic acid type A. Viral species B. Taxonomy C. Morphology D. Viral Characteristics
Taxonomy
True or False During lysogeny, the phage remains latent
True
True or False During the maturation of enveloped viruses, the envelope is acquired through budding from the host cell membrane
True
True or False Virus spikes are used for attachment to the host cell
True
True or False Viruses contain DNA or RNA as their nucleic acid
True
True/False Nucleic acid can be either linear or circular
True
Which of the following is NOT characteristic of viruses? A. Viruses are unaffected by antibiotics. B. Viruses have either DNA or RNA, but not both. C. Viral nucleic acid is surrounded by a plasma membrane. D. Viruses lack an ATP-generating mechanism.
Viral nucleic acid is surrounded by a plasma membrane
A completed, fully developed, infectious viral particle composed of nucleic acid and surrounded by a protein coat outside of a host cell is called: A. Caspid B. Viroid C. Prion D. Virion
Virion
Cause the synthesis of specialized structures that can transfer the viral nucleic acid to other cells A. Fungi B. Virus C. Protozoa D. Helminth
Virus
Contain a protein coat that surrounds the nucleic acid enclosed by and envelope A. Fungi B. Virus C. Helminth D. Protozoa
Virus
Contain a single type of nucleic acid A. Virus B. Helminth C. Protozoa D. Fungi
Virus
Multiply inside living cells by using the synthesizing machinery of the cell A. Protozoa B. Virus C. Helminth D. Fungi
Virus
Which statement about viruses is FALSE? A. The genome of a virus can be either DNA or RNA, depending on the particular virus. B. Viruses will usually infect any available cell, regardless of the cell type. C. Viruses are active only when inside a cell. D. Viruses always have a protein coat.
Viruses will usually infect any available cell, regardless of the cell type
Which do all viruses have ? A) a capsid B) an envelope
a capsid
To what does the term viral species refer? A. a group of viruses sharing the same disease symptoms B. a group of viruses sharing the same genetic information and structure C. viruses grouped according to their susceptibility to antibiotics D. a group of viruses that are reproductively isolated E. viruses grouped according to growth on selective media
a group of viruses sharing the same genetic information and structure
Which of these causes a disease called Creutzfeldt-Jakob disease? A) a virion B) a prion
a prion. Prions are infectious proteins that cause a number of neurological diseases and a virion is another name for a complete virus.
Which of these causes a disease called Creutzfeldt-Jakob disease? A) a viroid B) a prion
a prion. Prions are infectious proteins that cause a number of neurological diseases.
What is the complete assembled virus known as A) a viroid B) a virion.
a virion. A virion is the complete virus.
Which of the following are possible strategies for treating viral infections? A. blocking viral attachment to host cell receptors B. blocking uncoating of the virus after entry C. blocking insertion of viral DNA into the host cell chromosomes D. blocking biosynthesis of viral nucleic acids. E. all of the above
all of the above
Prions cause disease by __________. A. altering normal proteins B. altering genes C. activity of a reverse transcriptase D. causing transcription and translation of abnormal proteins
altering normal proteins
The combination of lipids, proteins, and carbohydrates covering the protein coat of a virus is A) an envelope B) a capsid
an envelope. The envelope may cover the capsid of some viruses called enveloped viruses.
What is the term for a virus that infects bacteria?
bacteriophage
Some viruses leave a cell by pushing through the cell membrane (rather than lysing the cell). When this happens, a portion of the membrane wraps round the viral capsid, becoming the envelope. What is the name for this process? A. lysogeny B. biosynthesis C. budding D. conjugation
budding
The protein coat of a virus is called the __________. A. capsid B. capsomere C. envelope D. viral membrane
capsid
Cell lines derived from transformed (cancerous) cells are called ________. A. embryonated B. primary cell lines C. continuous cell lines D. plaques E. monolayers
continuous cell lines
Provides a way of studying a disease's progression A. cultivated in a living animal B. Cultivated in cell culture C. Cultivated in embryonated poultry eggs
cultivated in a living animal
The only way to measure the body's immune response to a particular virus A. cultivated in a living animal B. Cultivated in cell culture C. Cultivated in embryonated poultry eggs
cultivated in a living animal
Prion diseases can be acquired in all of the following ways except by ________. A. transplantation B. inherited C. direct contact D. ingestion E. contaminated surgical instruments
direct contact
Which of these factors is NOT used in classifying viruses? A. morphology B. disease symptoms C. host range D. genome
disease symptoms
Some viruses have a membrane-like structure on their surface, composed of lipids, proteins, and carbohydrates. This is called a(n) __________. A. capsid B. core C. capsule D. envelope
envelope
Which of the following is the preferred method for cultivating many animal viruses? A. growing them in animal cell cultures B. growing them in bacteria C. inoculating appropriate laboratory animals D. growing them on highly enriched agar media
growing them in animal cell cultures
Viruses are detected and identified by: A. lysogenics B. Capsomeres C. how they invade a cell D. how they react to antibodies
how they react to antibodies
During which stage do the capsomere proteins and nucleic acid assemble to form virons? A) biosynthesis B) maturation
maturation. Maturation occurs when new viral particles are forming prior to release from the cell.
The following steps occur during bacteriophage replication. What is the second step? A. lysis B. attachment C. biosynthesis D. penetration
penetration
During the bacteriophage lysogenic cycle, ________. A. no attachment occurs B. the burst time is shortened C. the host cell lyses, releasing new virions D. new phage DNA is synthesized E. phage DNA is inserted into the host chromosome
phage DNA is inserted into the host chromosome
The agent causing mad cow disease is a A) viroid B) prion
prion. These infectious proteins cause a variety of spongiform encephalopathies.
What is the name given to the viral DNA incorporated into a lysogenic cell? A. prophage B. latent phage C. bacteriophage D. oncogenic virus
prophage
A virus may contain any of any of the following except ________. A. lipid envelope B. ribosomes C. spike proteins D. ssRNA E. capsid proteins
ribosomes
What is the term for the projections from the surface of the viral envelope that attach to host cells?
spikes
Which part of the virus generally consists of some combination of lipids, proteins, and carbohydrates? A) the capsomeres B) the envelope
the envelope
After the attachment and entry of a virus into a host cell, what is the next step in the multiplication of animal viruses? A. release B. transcription of "early" genes C. uncoating D. transcription of "late" genes E. synthesis of capsid proteins
uncoating
Bacteriophages A. host cells the virus can infect B. virus that infect bacteria C. and immature bacterial cell D. a phase of the lytic cycle
virus that infect bacteria