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