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