Microbio Unit 5 (Viruses)

Polysaccharide network

Protein coat known as a capsid

Double membrane

Cytoskeleton proteins forming a ring

The extracellular environment

Host nuclear membrane

Translation of viral genes

Host plasma membrane

tetrahedral

helical

icosahedral

complex

double-stranded RNA

single-stranded RNA

triple-stranded DNA

single-stranded DNA

Involve a specific host

Prefer certain tissue or cell types (tropism)

Can be lytic or lysogenic

All of the above

Prevent viral attachment to T helper cells

Allow attachment, but prevent replication

Allow replication, but prevent budding

Allow budding, but virions would be noninfectious

Copies genomic RNA to DNA

Makes few mistakes during replication

Degrades DNA after replication

Has protease activity

env codes for matrix & capsid proteins

gag codes for reverse transcriptase

env is cleaved by viral protease into gp160

pol codes for a polyprotein, processed by viral protease

Turbidity (opaqueness) on a bacterial lawn

Clearings (plaques) on a bacterial lawn

Inability to pass through a membrane filter

Growth on mammalian cells

Entry into the lytic cycle rather than lysogenic cycle

Integration of the phage into the bacterial genome

Prevention of viral DNA injection

Blockade of theta replication