micro ch 6
Viroids are infectious agents that consist of _____. Multiple choice question. DNA only RNA and protein protein only RNA only
RNA only
Cells from cancerous tumors actively spread throughout the body in a process known as _____. Multiple choice question. oncogenesis metastasis differentiation lysogeny
metastasis
Select the four cellular structures that can be the source of viral envelopes. Multiple select question. nuclear membrane Golgi apparatus mitochondria ribosome endoplasmic reticulum plasma membrane
nuclear membrane Golgi apparatus endoplasmic reticulum plasma membrane
An acellular infectious agent that must replicate within a host cell is a(n)
virus
In the context of virus replication, fusion with the host cell membrane, injection of nucleic acid, and endocytosis are the three modes of _____. Multiple choice question. virus release from host cells virus assembly inside host cells virus entry into host cells synthesizing viral nucleic acids
virus entry into host cells
Once a virus enters the cytoplasm of a host cell, which step would occur next? Multiple choice question. Synthesis of ATP Virion assembly Host cell lysis Replication of the viral genome
Replication of the viral genome
A host cell that contains a ________ , the nucleic acid of a temperate phage, can divide many times.
prophage
Which two of the following are examples of lysogenic conversion? Multiple select question. Salmonella producing novel lipopolysaccharides T4 phage suddenly infecting more than one bacterial species Fusion of T-even phage with T4 phage Corynebacterium diphtheria causing diphtheria
Salmonella producing novel lipopolysaccharides Corynebacterium diphtheria causing diphtheria
What viral life cycle step generally occurs after the virus has uncoated? Multiple choice question. Entry Attachment Self-assembly Synthesis
Synthesis
Which of the following viral structures comes principally from the host cell? Multiple choice question. Capsid Envelope Nucleic acids Tail fibers
Envelope
What name is given to a viral capsid that is shaped like a hollow tube with protein walls? Multiple choice question. Helical Complex Icosahedral Pleomorphic
Helical
Viral specificity for a host cell type is dependent on ____. Multiple select question. Host receptor Viral ligand Host metabolism Viral nucleic acid
Host receptor Viral ligand
Select the two most common forms of viral release. Multiple select question. fusion endocytosis budding lysis phagocytosis
budding lysis
Viral envelopes can often give a collection of identical viruses variable shapes. Such viruses are referred to as ______. Multiple choice question. complex icosahedral helical pleomorphic
pleomorphic
Which of the following viral structures is composed of just the protein that surrounds the nucleic acid? Multiple choice question. Nucleocapsid Capsid Protomer Viral envelope
Capsid
Which of the following viral structures is composed of just the protein that surrounds the nucleic acid? Multiple choice question. Protomer Nucleocapsid Capsid Viral envelope
Capsid
Viroids cause disease in what type of host? Multiple choice question. archaea plants bacteria fungi
plants
Which of the following describes a tumor resulting from unregulated abnormal new cell growth and reproduction of a similar cell type? Multiple choice question. Neoplasia Cancer Anaplasia Cytopathic effects
Neoplasia
Which two of the following viral activities occurs during "viral entry"? Multiple select question. Replication Budding Lysis Penetration Uncoating Self-assembly
Penetration Uncoating
Which is NOT true about lysogenic bacteria? Multiple choice question. They would normally stop dividing. They could become pathogenic. When they reproduce, they also copy the viral DNA. They can reproduce normally.
They would normally stop dividing.
True or false: The cell membrane is the only host cell structure from which enveloped viruses obtain their envelope. True false question.TrueFalse
false
the energy for viral replication, gene expression, and nucleocapsid assembly comes from _____. Multiple choice question. host ATP the proton motive force breakdown of the viral capsid viral ATP
host ATP
Budding is best described as Multiple choice question. how naked viruses leave their host cell how viruses replicate their circular genomes how enveloped viruses acquire their membranes how viruses fuse two or more virions together
how enveloped viruses acquire their membranes
What name is given to the process that leads a lysogenic virus to transition to the lytic cycle? Multiple choice question. induction initiation lysogenic conversion transduction
induction
A helical capsid _____. Multiple choice question. is found only on double-stranded DNA viral genomes is shaped like a hollow tube with protein walls is wound around a protein core denatures when the virus replicates
is shaped like a hollow tube with protein walls
What is the generalized term used to describe the viral component that is used to bind to a host cell for attachment? Multiple choice question. Ligand Protomer Envelope Capsid
ligand
Virus will attach to host cells via a viral ______ and a host receptor.
ligand (spike or glycoprotein)
A viral envelope is composed of primarily ____. Multiple choice question. sugars proteins lipids nucleic acids
lipids
Most viruses will leave a host cell by bursting the cell, a process called _______ , or by pushing through the cell membrane while taking some of that membrane with it, a process called _______.
lysis budding
Bacteria infected by temperate phages are called ______ bacteria. Multiple choice question. heat-shocked lytic lysogenic transfected
lysogenic
When a temperate phage integrates its genome into a host genome, the relationship between the phage and the host is termed ____ .
lysogeny
Viruses that lack a viral envelope are often called ____. Multiple choice question. protomers phage virions naked
naked
A tumor is a growth or lump of tissue resulting from _______ , which means unregulated abnormal new cell growth and reproduction of a similar cell type.
neoplasia
The simplest viruses consist of nucleic acid surrounded by a protein coat. This composite structure of viral nucleic acid and protein is called a ______. Multiple choice question. nucleocapsid protomer capsid viroid
nucleocapsid
Normal cellular genes that result in cancer when mutated are called proto-
oncogenes
The main difference between virulent phage and temperate phage is that virulent phage _____. Multiple choice question. always integrate into the host genome alternate between temperate and virulent only have a lytic cycle always cause disease
only have a lytic cycle
Infectious agents composed entirely of protein are called _____. Multiple choice question. viroids prions satellites viruses
prions
The nucleic acid of a temperate phage that is either integrated into the host cell's genome, or remains free in the cytoplasm, is called a _____. Multiple choice question. virulent phage lysogen prophage mesophage
prophage
Which two of the following components make up a viral nucleocapsid? Multiple select question. cell wall peptidoglycan protein coat nucleic acid envelope
protein coat nucleic acid
The main difference between proto-oncogenes and tumor suppressor genes is that proto-oncogenes are normal cellular genes, tumor suppressor genes are not. proteins encoded by proto-oncogenes normally stimulate cell division; proteins encoded by tumor suppressor genes normally inhibit cell division. tumor suppressor genes are normal cellular genes, proto-oncogenes are not. proteins encoded by proto-oncogenes normally inhibit cell division; proteins encoded by tumor suppressor genes normally stimulate cell division.
proteins encoded by proto-oncogenes normally stimulate cell division; proteins encoded by tumor suppressor genes normally inhibit cell division.
Capsids are generally composed of repeating proteins subunits called
protomer
During T4 bacteriophage release, holin will ____. Multiple choice question. put holes in the cell membrane hydrolyze the peptidoglycan cell wall disrupt the nucleus acidify the cytoplasm
put holes in the cell membrane
Virus will attach to host cells via a viral ligand and a host
receptor
What term describes the host cell component that a virus will bind for attachment? Multiple choice question. receptor capsomer peplomer spike protein
receptor
Which two of the following are correct descriptions of viroid structure? Multiple select question. relatively short; about 250 to 400 nucleotides long dsDNA with associated histones nucleic acid surrounded by a lipid envelope circular ssRNA ssDNA with histone-caps
relatively short; about 250 to 400 nucleotides long circular ssRNA
The last step in the replication cycle of a virus is generally called
release
Which of the following may be composed of RNA or DNA, encode one or more proteins, and must have a "helper" virus to replicate? Multiple choice question. viroids phages prions satellites
satellites
The viral-encoded proteins that project from a viral envelope surface are called ____. Multiple choice question. tail fibers spike proteins fimbriae flagella
spike proteins
Bacteriophages that can integrate their genome into the host genome are called _____ phages.
temperate
Which of the following describe a bacteriophage that may lyse its host cell, or remain within the cell without lysing it? Multiple choice question. temperate virulent pleomorphic prophage
temperate
Enveloped viruses gain their envelope from ____. Multiple choice question. biosynthesis and secretion the host cell membrane water absorbed into the capsid the environment
the host cell membrane
Spikes, or peplomers, are _____. Multiple choice question. virally-encoded proteins that project from the envelope surface virally-encoded phospholipids that comprise the envelope host-encoded phospholipids that comprise the envelope host-encoded proteins that project from the envelope surface
virally-encoded proteins that project from the envelope surface
A complete virus particle is called a(n)
virion
A complete virus particle is referred to as a ____. Multiple choice question. virus virion bacteriophage viroid
virion
An infectious agent composed of only RNA is called a(n)
viroid
Which type of genome would seem simplest to replicate in a host cell? Multiple choice question. RNA DNA
DNA
Which two of the following have direct involvement with viral attachment? Multiple select question. Viral ligand Host receptor Viral nucleic acid Host mitochondrion
Viral ligand Host receptor
Which of the following best defines a virulent phage? Multiple choice question. A virus that remains in the host cell indefinitely A virus that always progresses to lysis of the infected cell A virus that is highly infectious to animals A virus that carries DNA fragments from the host cell
A virus that always progresses to lysis of the infected cell
Which of the following best defines a temperate phage? Multiple choice question. A virus that can integrate its genome into the host genome. A virus that is temperature-dependent on whether it infects a cell or not. A virus that is highly resistant to temperature. A virus that is temperature-dependent on whether it lyses a cell or not.
A virus that can integrate its genome into the host genome.
Which two of the following statements regarding virus structure are correct? Multiple select question. Viruses have a lipid bilayer separating the genome from the capsid. All viruses contain ATP as their energy storage molecule. All viruses have a form of nucleic acid, either DNA or RNA. Viruses do not have a cytoplasm.
All viruses have a form of nucleic acid, either DNA or RNA. Viruses do not have a cytoplasm.
Which of the following best describes a virus? Multiple choice question. A cellular infectious agent that can only replicate within a host cell. An acellular infectious agent that can only replicate within a host cell. A pathogen that can infect a host cell but can also replicate independently. A group of acellular agents that only infect human cells.
An acellular infectious agent that can only replicate within a host cell
________ _______ is when a temperate phage causes a change to the phenotype of an infected bacterial cell.
Lysogenic Conversion
Lysogenic conversion occurs when ____. Multiple choice question. a phage causes nuclear fusion of two bacterial cells a phage interrupts bacterial conjugation two different phage infect the same bacterial cell a phage gives new phenotypic properties to a bacterial cell
a phage gives new phenotypic properties to a bacterial cell
Which two stages of viral replication occur after viral synthesis? Multiple select question. assembly attachment entry release penetration
assembly release
The function of viral spike proteins is to ____. Multiple choice question. attach to a host cell surface promote viral genome replication puncture host cell membranes aid in capsid assembly
attach to a host cell surface
The first step in the viral life cycle is ____. Multiple choice question. assembly attachment release synthesis
attachment
If a tumor cells remain in place to form a compact mass, the tumor is said to be _____. Multiple choice question. differentiated oncogenic benign metastatic
benign
The protein coat that surrounds the viral nucleic acid is called the
capsid
Either five or six protomers usually combine to make each _____ in icosahedral viral capsids.
capsomer
Icosahedral capsids are composed of repeating ring- or knob-shaped protein subunits called ____. Multiple choice question. capsomers promoters envelopes protomers
capsomers
The best definition of cytopathic effects caused by a viral infection of eukaryotic cells is Multiple choice question. lysis and death of host cells destruction of infected cells by the host immune system virus replication within the cytoplasm of infected cells changes or abnormalities in infected cells that are distinct from lysis
changes or abnormalities in infected cells that are distinct from lysis
Viral symmetry that is both icosahedral and helical and possibly other symmetry is collectively referred to as ____ symmetry. Multiple choice question. pleomorphic geometric complex radial
complex
Which two of the following components are not found in viruses? Multiple select question. genome structural proteins cytoplasm ribosomes
cytoplasm ribosomes
In contrast to viral genomic DNA, which may be dsDNA, ssDNA, dsRNA, or ssRNA, cellular genomes are always _____ Multiple choice question. ssDNA dsRNA ssRNA dsDNA
dsDNA
Which of the following genomes could be included within a single virus? Multiple select question. both RNA and DNA both ssDNA and ssRNA dsRNA dsDNA ssRNA both dsRNA and dsDNA ssDNA
dsRNA dsDNA ssRNA ssDNA (not both option bc viruses cannot have both DNA & RNA within the virion as heritable material)
Select the three methods used by viruses to gain entry into host cells. Multiple select question. entry of the viral envelope only, leaving the capsid outside the cell endocytosis of the virus into the cell injection of viral nucleic acid into the cell fusion of the viral envelope with host cell membrane fusion of the viral capsid with the host cell lysosomes
endocytosis of the virus into the cell injection of viral nucleic acid into the cell fusion of the viral envelope with host cell membrane
The second step of the viral life cycle is ____. Multiple choice question. release synthesis entry attachment
entry
The outer lipid membranous layer found surrounding some viruses is called the
envelope
Viruses with a lipid membrane are often called ____. Multiple choice question. phage naked virions enveloped
enveloped