Chapter 7 micro

A single virion could contain a genome of ______.

DNA only RNA only

A virus that has a membranous layer external to the nucleocapsid is called a(n)________ virus.

Enveloped

True or false: Viruses which can lead to cancer are termed carcinoviruses.

False

Different viruses can infect which of the following?

Human, bacterial, or plant cells

A geometric viral form having 20 faces and 12 corners is termed a(n)____

Icosahedron

What is the term which describes a geometric viral form having 20 faces and 12 corners?

Icosahedron

What name is given to a phage "type" which can incorporate itself into the host genome?

Temperate

A proteinaceous infectious agent associated with spongiform encephalopathies is called a(n) .

Prion

What term is used to describe a virus type which depends on other viruses for replication?

Satellite virus

Which structure immediately encloses viral nucleic acid?

The capsid

Which term describes the integration of an oncogenic virus that changes mammalian host DNA?

Transformation

Any virus that specifically infects bacteria is called a(n)

bacteriophage

n a lytic infection of a bacteriophage, the host cell ______, whereas in a lysogenic infection of a bacteriophage, the host cell ______.

bursts when new viruses leave the cell; is not destroyed immediately

The structure directly surrounding the viral nucleic acid is the, ________a coat of proteins.

capsid or nucleocapsid

A virus may persist in cells in an inactive state, periodically becoming reactivated, and is said to be in a(n) ______ state.

chronic latent

Viruses ______ depend on a host cell for replication.

completely

To describe viruses which have a non-icosahedral or non-helical arrangement of capsomer proteins we use the term

complex

Multinucleated cells, giant cells, and inclusion bodies are examples of ________effects on cells previously infected with a virus.

cytopathic

Virus-induced damage to the cell that alters its microscopic appearance is termed ______.

cytopathic effect

Which term is used to describe the process when a virus is engulfed by a cell in a vacuole or vesicle?

endocytosis

Which term is used to describe the phospholipid bilayer found surrounding the capsid of some viruses?

envelope

True or false: Antibiotics are an effective treatment for most viral infections.

false

Viral transformation implies that the ______.

host DNA is changed

Capsids that are rigid and tight are typical of ______ helical viruses, while capsids of ______ helical viruses are flexible and loose.

naked; enveloped

Which of the following best describes viruses?

obligate intracellular parasites

Which cellular organisms can viruses infect?

plants, protozoa, fungi, bacteria, animals

Phage DNA that is latently incorporated into the bacterial host genome is called a(n)

prophage

When viruses lose their envelope during penetration into a host cell, or when the envelope/capsid are dissolved within a vacuole, it is referred to as_____

uncoated

A fully formed viral particle, capable of infecting a host cell, is called a ______.

virion

Which of the following is composed of only RNA?

viroid

Which of the following describe an animal virus that has integrated its genome into the host cell's genome?

Provirus

In the viral multiplication cycle, capsids and genetic material are packaged into virions during the step.

assembly

In the viral multiplication cycle, capsids and genetic material are packaged into virions during the_________________ step. Please give the specific term for this step.

assembly or maturation

In which way do enveloped viruses leave their host cell?

budding

When cells are infected, yet show no cytopathic effects, it is referred to as a(n)__________ infection.

persistent or latent

Identify all the components of the nucleocapsid.

nucleic acid and capsid

Collectively, the capsid and nucleic acid of a virus are referred to as the

nucleocapsid

There are two ways in which newly assembled viruses can be released from host cells. Enveloped viruses are usually released through _______________(exocytosis), while naked viruses are typically released through__________________ (rupture).

budding lysis

A ___________occurs when a virus induces multiple cells to fuse making a large multinucleated cell.

syncytium or syncytia

An acellular agent composed of nucleic acid surrounded by a protein coat is called a(n)____

virus

The viral process of attaching to a host cell receptor prior to infecting the cell, is called

Adsorption

Which is the correct term to describe viral adherence to a host cell receptor?

Adsorption

It is well known that chemicals called ___________have no effect on treating viral infections.

Antibiotics

Which of the following describes the various viral parts coming together to produce virions?

Assembly

What term is used to specifically describe the types of viruses that infect bacteria?

Bacteriophage

Identify the commonalities between temperate phages and lytic phages.

Biosynthesis of viral components Adsorption Penetration Assembly Release

Which is closest in physical proximity to the nucleic acid of a virus?

Capsid

A protein subunit that forms a viral capsid is called a(n)_____

Capsomeres

Which of the following is the monomeric unit of a viral capsid?

Capsomeres

Which type of capsids are composed of multiple protein types and nonsymmetrical shapes?

Complex

Which of the following is a mass of viruses or damaged organelles due to the cytopathic effect of a viral infection?

Inclusion body

Which term refers to the persistence of bacteriophages within host cells?

Lysogeny

What is the common name of bovine spongiform encephalopathy?

Mad cow disease

At minimum, all viruses are composed of Blank______.

Nucleic acids Proteins

During its replication a DNA virus enters the ________of the host cell, where several genes are transcribed into messenger RNA.

Nucleus

Viruses that lead to cancer in infected hosts are called

Oncogenic

Which of the following best describes the relationship between viruses and their host cell?

Parasitism

True or false: Most infections caused by animal viruses do not result in death of the host organism.

True

True or false: The viral envelope and capsid are the same thing.

True

True or false: Viruses can contain either DNA or RNA, but not both.

True

Which term describes the process of a virus losing its capsid and exposing viral nucleic acids to the immediate environment?

Uncoating

Which facts best support the position that viruses are not living organisms?

Viruses cannot reproduce on their own. Viruses do not have any means of independent metabolism.

Which viral stage occurs first?

adsorption

Lysogeny is best described as ______.

integration of the viral genome into the host chromosome

Typically, naked helical viruses are _____ flexible than enveloped helical viruses.

less

When a bacterium acquires a new trait from a temperate phage____________, conversion has occurred.

lysogenic

When a temperate phage infects a bacterium, giving the bacterium new traits, this is called _____.

lysogenic conversion

Viral infections that kill host bacterial cells soon after entering are called ______ infections, whereas viral infections that delay killing the host bacterial cells are called ______ infections.

lytic; lysogenic

All viruses are composed of at least nucleic acid covered by a coating comprised of_____

protein, proteins, or capsomers

Which of the following best describes a prion?

proteinaceous infectious agent

The stage of an animal virus life cycle which is integrated into the host cell's genome is

provirus

In a chronic latent state, a virus will ______.

remain dormant in cells for years

A noncellular infectious form that depends on other viruses for replication is known as a(n) __________virus.

satellite

Most human viral infections are _____.

self-limiting

Viral glycoproteins that protrude from the viral envelope and attach to host cell receptors are termed

spikes

What term is used to describe the viral proteins which protrude from the envelope and aid in attachment to host receptors?

spikes

Identify which of the following statements represent activities that viruses cannot do.

Consume food Replicate outside of a cell

In the disease condition known as bovine spongiform encephalopathy, what does "bovine" mean?

Cow

True or false: Bacteriophages infect eukaryotic and prokaryotic microorganisms.

False

A cell harboring a virus that is not causing cytopathic effects is characteristic of which type of infection?

Persistent infection

Bacteriophages can infect which of the following?

Prokaryotes only

Which of the following is used to describe the phage DNA that is latently incorporated into the bacterial host genome?

Prophage

Which of the following is a multinucleated cell due to the cytopathic effect of a viral infection?

Syncytium

During which of the folowing phases of the multiplication cycle of RNA is the +ssRNA replicated by host machinery into -ssRNA?

Synthesis

An infectious agent that lacks a capsid and merely consists of a strand of RNA is called a(n)

Viroid

One type of cytopathic effect of a viral infection results in the presence of masses of viruses or damaged organelles, called _________bodies.

inclusion

A bacteriophage that incorporates itself into the host genome as a lysogenic prophage is a(n) ______________phage.

temperate

Phages that enter the prophage state are_____________ phages, while ____________phages burst the host cell.

temperate or lysogenic

A fully formed, single virus particle is known as a(n)______

virion