Intro to Viruses I (Bosque) Flashcards
Name 4 shapes of viruses
- icosahedral nucleocapsid
- enveloped icosahedron
- helical, non-enveloped
- helical, enveloped
T:F - viruses can be RNA or DNA and ds or ss.
True!
A ss DNA virus is _____ (enveloped?)
non-enveloped
A ds RNA virus is _____ (enveloped?)
non-enveloped
Name 5 steps of viral life cycle
- binding
- entry
- replication of viral nucleic acid
- viral assembly and release
2 methods of 1. binding
- absorption: virion attaches to host, releases inner tube, proteins degrade membrane, DNA from phage passed into host
- receptor mediated: enveloped viruses uses envelope to bind to receptors, trigger fusion, and endocytosed
What is the purpose of the entry phase?
remove capsid that surrounds DNA
2 types of viral infection
lytic and lysogenic
Lytic cycle
viral genome replicated and transcribed to make vial progeny, which is released by lysis of host cell
Lysogenic cycle
viral genome integrates into host chromo as prophage, which is replicated w/ host chromo and passed down
Is viral DNA linear or circular?
linear when injected but circulates
Describe 2 methods of viral assembly and release
Phage: encode protein that degrades membrane of bacteria so bacteria dies and virus spreads out
Budding: bud from surface of cell, which won’t kill cell
Name 4 general patterns of disease
acute, chronic, latent, slow
Prodrome
nonspecific early symptoms (fever, aches, chills)
Name major routes of virus entry into host
skin, oropharynx, GI, respiratory tract, genitourinary
