viral properties and disease Flashcards
define the nature of viruses, and summarise a generic life cycle of a virus, explaining its parasitic nature in relation to the host cell
define virus
infectious obligate (cannot complete life-cycle without being inside host cell) IC parasite
what is a viruses’ genome made of
DNA or RNA
how big is a virus
very small (100nm)
4 features of a disease causing virus
must be large in numbers of disease but not healthy animals; isolated and grown outside body in pure culture; when injected, causes same disease; recovered from host, isolated, compared to original and found to be identical
4 stages of generic viral replication cycle
virus finds cell and attaches to cell surface (proteins bind to receptors) → virus “uncoats” so genome can gain access to necessary machinery, especially ribosomes → make copies of own genome using polymerase → synthesised genomes and proteins assemble together to bud out of cell
generic viral replication cycle diagram
diagram
