Virus - Structure/Function Flashcards
How much of our genome is viral?
8% is endogenous retroviruses due to ancestral infection.
Virus
Simple, miniscule, infectious, obligate intracellular parasite comprised of genetic material surrounding by a capsid and/or enveloped derived from host cell.
What is a virus composed of?
Nucleic acids and proteins
What is the base mechanism of viruses?
Hijack metabolic functions of the cell and produce their own protein viruses.
Why are viruses host obligates?
They have to hijack machinery.
iWhat genetic material do viruses contain?
ssDNA/RNA or dsDNA/RNA
What is an example of a small viral genome?
Influenza virus has 11 genes
What is the average size of viruses?
1-1000 micrometres.
What are examples of size scale of viruses?
Poliovirus same as ribosome
Rhiovirus 20-30 nm in diametre
Bacteriophage M52 24nm in size
Mimivirus 750nm
Pandoravirus 2.9MB genome
What is the difference between virus and virion?
Intracellular and extracellular for replicaiton and transmission respectively.
How are viral structures determined?
Cry-electron microscopy
Electron microscopy
X-Ray Crystallography
Nuclear Magnetic Resonance Spectroscopy
What is the structre of the viron?
Centre nucleic acid surrounded by capsomers forming capsid, together the nucleocapsids
What determines virus shape?
Arrangement of capsomers
What are the two types of capsomers?
Pentamers-5 protein subunits
Hexamers -6 protein subunits
What are the three categories of capsid shape?
Helical
Polyhedral
Binal