acellular
lacking cells
acute disease
disease where the symptoms rise and fall within a short period of time
asymptomatic disease
disease where there are no symptoms and the individual is unaware of being infected unless lab tests are performed
attenuation
weakening of a virus during vaccine development
AZT
anti-HIV drug that inhibits the viral enzyme reverse transcriptase
back mutation
when a live virus vaccine reverts back to it disease-causing phenotype
bacteriophage
virus that infects bacteria
budding
method of exit from the cell used in certain animal viruses, where virions leave the cell individually by capturing a piece of the host plasma membrane
capsid
protein coating of the viral core
capsomere
protein subunit that makes up the capsid
cell necrosis
cell death
chronic infection
describes when the virus persists in the body for a long period of time
cytopathic
causing cell damage
envelope
lipid bilayer that envelopes some viruses
fusion
method of entry by some enveloped viruses, where the viral envelope fuses with the plasma membrane of the host cell
gall
appearance of a plant tumor
gene therapy
treatment of genetic disease by adding genes, using viruses to carry the new genes inside the cell
group I virus
virus with a dsDNA genome
group II virus
virus with a ssDNA genome
group III virus
virus with a dsRNA genome
group IV virus
virus with a ssRNA genome with positive polarity
group V virus
virus with a ssRNA genome with negative polarity
group VI virus
virus with a ssRNA genomes converted into dsDNA by reverse transcriptase
group VII virus
virus with a single-stranded mRNA converted into dsDNA for genome replication
horizontal transmission
transmission of a disease from parent to offspring
hyperplasia
abnormally high cell growth and division
hypoplasia
abnormally low cell growth and division
intermittent symptom
symptom that occurs periodically
latency
virus that remains in the body for a long period of time but only causes intermittent symptoms
lysis
bursting of a cell
lysogenic cycle
type of virus replication in which the viral genome is incorporated into the genome of the host cell
lytic cycle
type of virus replication in which virions are released through lysis, or bursting, of the cell
matrix protein
envelope protein that stabilizes the envelope and often plays a role in the assembly of progeny virions
negative polarity
ssRNA viruses with genomes complementary to their mRNA
oncogenic virus
virus that has the ability to cause cancer
oncolytic virus
virus engineered to specifically infect and kill cancer cells
pathogen
agent with the ability to cause disease
permissive
cell type that is able to support productive replication of a virus
phage therapy
treatment of bacterial diseases using bacteriophages specific to a particular bacterium
positive polarity
ssRNA virus with a genome that contains the same base sequences and codons found in their mRNA
prion
infectious particle that consists of proteins that replicate without DNA or RNA
productive
viral infection that leads to the production of new virions
prophage
phage DNA that is incorporated into the host cell genome
PrPc
normal prion protein
PrPsc
infectious form of a prion protein
replicative intermediate
dsRNA intermediate made in the process of copying genomic RNA
retrovirus
virus with an RNA genome that must be reverse transcribed into DNA before being incorporated into the host cell genome
reverse transcriptase
enzyme found in Baltimore groups VI and VII that converts single-stranded RNA into double-stranded DNA
vaccine
weakened solution of virus components, viruses, or other agents that produce an immune response
vertical transmission
transmission of disease from parent to offspring
viral receptor
glycoprotein used to attach a virus to host cells via molecules on the cell
virion
individual virus particle outside a host cell
viroid
plant pathogen that produces only a single, specific RNA
virus core
contains the virus genome