Microbiology Chapter 6 LearnSmart

At minimum, viruses are composed of nucleic acid covered by a coating comprised of ____________

protein

"Virus" is Latin for ______. poison cow in glass in living organisms agent

poison

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

Capsid

Which structure immediately encloses viral nucleic acid? Envelope Capsid Cell wall

Capsid

A(n) ___________is a protein subunit that forms the viral capsid.

Capsomere

Which of the following is the monomeric unit for a viral capsid? Fiber Facet Capsomere Amino acid

Capsomere

At minimum, all viruses are composed of Carbohydrates Lipids Nucleic acids Proteins

Nucleic acids Proteins

E. coli has about 4,000 genes in its chromosome. A virus that infects E. coli would be expected to have about ______ genes in its chromosome. 10 millions 4,00

10

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

Capsid

Which term is used to describe the phospholipid bilayer found surrounding the capsid of some viruses? Envelope Vacuole Cell membrane Phagosome

Envelope Many viruses possess an outer covering called the envelope, usually a modified piece of a host cell membrane (phospholipid bilayer).

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

False The viral envelope is composed of phospholipids while the capsid is composed of capsomer proteins.

Which of the following term describes the total nucleic content of a virus? Gene mRNA DNA Genome Capsid Chromosome

Genome

Different viruses can infect which of the following? Bacterial cells only Human, bacterial, or plant cells Plant cells only Human cells only

Human, bacterial, or plant cells

What is the term which describes a geometric viral form having 20 faces and 12 corners? Complex Diamond Icosahedron Helical Facet

Icosahedron

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

Less

A ____________virus does not have an envelope surrounding its capsid.

Naked

Identify all the components of the nucleocapsid. Scaffolding proteins Polymerase Nucleic acid Envelope Capsid

Nucleic acid Capsid

The __________refers to the capsid and nucleic acid of a nonenveloped virus.

Nucleocapsid

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

Prion

Capsomeres are composed of ___________ (Hint: it is a macromolecule)

Protein

Which macromolecule composes capsomeres? Lipids Nucleic acids Carbohydrates Proteins

Proteins

A single virion could contain a genome of RNA only DNA only neither RNA or DNA both RNA and DNA

RNA only DNA only A virion must contain either RNA or DNA.

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 Capsomeres Nucleocapsid

Spikes

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

True

True or false: Viral nucleic acid may be single-stranded or double-stranded DNA or RNA.

True

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

True

True or false: Viruses are among the smallest infective agents. True False

True Reason: Most viruses are 1000X smaller than bacteria.

Identify the smallest pathogenic agent. Fungal cell Virion Bacterial cell Helminth

Virion

Which of the following statements regarding the membrane on an enveloped virus is true? The viral envelope is not a lipid bilayer. The membrane is identical to the host cell membrane. Viruses insert their own proteins in the membrane. The membrane gives the virus particle a distinct shape.

Viruses insert their own proteins in the membrane.

Viral nucleic acids are ______. double stranded only either single-stranded or double stranded single-stranded only if RNA single-stranded only

either single-stranded or double stranded

The total nucleic acid content of a virus can be referred to as the viral ___________

genome

The total nucleic acid content of a virus can be referred to as the viral

genome/DNA

Viruses which have a series of rod-shaped capsomer proteins linked together forming a series of interconnected hollow discs are termed ______. diamond helical complex icosahedral

helical

Viruses which have a series of rod-shaped capsomer proteins linked together forming a series of interconnected hollow discs are termed ______. icosahedral helical complex diamond

helical

Two shapes of viral capsids are ______________ which resembles a bracelet; or ___________ which is a type of polyhedron.

helical icosahedral

A(n) _____________is a geometric viral form having 20 faces and 12 corners.

icosahedral

The number of genes in a viral genome is _____ the number of genes in a bacterial genome. much greater than much less than about the same as

much less than

A nonenveloped virus is also called a(n) ______ virus. icosahedral naked helical

naked

Capsids of ______ helical viruses are rigid and tight, while capsids of ______ helical viruses are flexible and loose. nonenveloped; naked naked; nonenveloped enveloped; naked naked; enveloped

naked; enveloped

In this image of a nucleocapsid, the macromolecule comprising the structure indicated by the arrow is ______. carbohydrate lipid nucleic acid protein

nucleic acid

Most human viral infections are ______. chronic for life lethal self-limiting

self-limiting

When an enveloped virus buds off the cell membrane, the membrane differs ______ from the host cell's membrane.

significantly

At a minimum, a viral genome must include genes for synthesizing the viral capsid synthesizing new ribosomes following infection regulating the actions of the host cell generating ATP for energy packaging the mature virus particles

synthesizing the viral capsid regulating the actions of the host cell packaging the mature virus particles

Genes for synthesizing the viral capsid, for regulating actions of the host cell, and for packaging the mature virus are found in the ______ genome. bacterial eukaryotic viral

viral

A fully formed virus that is able to establish an infection in a host cell is often called a ______. serotype prion virion hapten

virion

A single virus particle is known as a(n)_______

virion

Louis Pasteur coined for the latin word protist bacteria prion virus

virus

Louis Pasteur proposed the term ______, Latin for "poison", to denote a special group of infectious agents. virus protist bacteria prion

virus