Lecture 13: Virus Viroids, and Prions

what is the protein coat around a virus called

caspid

do viruses contain rna or dna

both

what is a virion

a nucleic acid

does a virion contain a caspid

yes

what are the capsids on virions made of

capsomere a protein subunit

what are cytopathic effects in viruses

the structural or morphological changes in host cells caused by viral replication, leading to cell death or dysfunction

what is the purpose of a serological test

to identify past exposure to pathogens, diagnose current or recent infections, detect antibodies

what is the lytic cycle

bacteriophage causes lysis and death of the host cell

what is the lysogenic cycle

phage injects the host cell with its DNA, the viral DNA integrates into the host’s chromosome to create a prophage, the host cell then replicates its infected DNA to its daughter cells

What is the attachment stage of the lytic cycle

the phage attaches by its tail fibers to the host cell

what is the penetration stage of the lytic cycle

the phage lysozyme opens the cell wall and injects infected DNA into the host cell which immediately kills it

what happens in the maturation stage in the lytic cycle

the assembly of the phage particles in the host cell

what happens in the release stage of the lytic cycle

the phage lysozyme breaks the host cell wall and the virions are released

what is generalized transduction

a type of horizontal gene transfer

what kind of bacterial genes can be transferred through generalized transduction

No specific kind

what is specialized transduction

Horizontal gene transfer but only specific genes can be transferred

what is sense strand RNA virus

the positive strand used directly as mRNA for immediate translation to create more positive strands to be packaged into a virus of a host cell

what is antisense strand RNA virus

the negative strand has to be transcribed into a positive one to be able to replicate positive mRNA, cannot immediately start replicating

how are prion diseases caused

when a normal host glycoprotein is converted into an infectious form, causes serious diseases, replication, and cell death