Classification & Replication of Viruses (2) Flashcards
Viruses can replicate only in _____ cells of animals, plants, and bacteria
living cells
Viruses are [intermediate/obligate] parasites that are metabolically inert when they are outside of their hosts
obligate
What do viruses rely on?
on the metabolic processes of their hosts to reproduce themselves
the viral diseases we see are due to host’s response to it
What is a prion?
a misfolded protein
not a virus, or any other recognized infectious agent
What do all prions affect?
the structure of the brain or other neural tissue
progressive
have no known effective treatment
always fatal
What are prions resistant to?
resistant to denaturation by chemical and physical agent
What is a proteopathy?
disease of structurally abnormal proteins
a prion is an example of this
What is the structure of a virus?
capsid
envelope
nucleic acid core (DNA or RNA)
Viral proteins are “_______” to their receptor proteins
lock and key - initiating infection
Both the ____ and ______ of a virus are antigenic, meaning that it causes an immune response triggered from antigens on the virus
capsid
envelope
What is the capsid made of?
glycoproteins - capsomeres
T/F: All viruses have an outer envelope
FALSE
What is the function of a capsid?
protect the fragile nucleic acid genome from:
physical damage
chemical damage
enzymatic damage
protein subunits
What are some properties of viruses?
heat sensitive
pH sensitivity
lipid solvents
chemicals
radiation and UV light
humidity
T/F: Enveloped viruses are generally less sensitive to lipid solvents and heat
FALSE - more sensitive
What are the 4 types of virus capsids?
isometric (icosahedral)
helical
complex
filamentous
What’s an example of an icosahedral capsid?
herpes virus
What is the structure of icosahedral capsid?
constructed of 20 equilateral triangular faces
What is the structure of a helical capsid?
tubular construction with the subunits arranged around the nucleic acid in a coil
What are examples of helical capsids?
rabies
flu
coronaviruses
What are the 2 symmetrical types of capsids?
icosahedral
helical
What are the 2 unsymmetrical capsid structures?
complex
filamentous
What are examples of complex viruses?
small pox
phage
What are filamentous viral capsid structures?
pleomorphic (able to assume different forms)
What’s an example of a filamentous capsid viral disease?
ebolavirus