mod 5 Flashcards
differences in structure of gram neg and gram positive bacteria
gram neg- inner plasma membrane, peptidoglycan, 2 periplasmic spaces, outer membrane, LPS
gram pos- inner plasma membrane, peptidoglycan, oe periplasmic space
does gram neg or gram pos have thicker peptidoglycan layer?
gram pos
what coulor do gram pos and gram neg turn when staining
neg- pink
pos- purple
gram neg or pos more resistant to antibiotics
gram neg, more components to cell wall make it more resistant
what si the role of LPS in gram neg
endotoxin. help with immune evasion, resistance etc
Difference between enveloped and non enveloped virusues
non envelopes- nucleic acid and capsule (nucleocapsid)
enveloped- nucleocapsid, matrix protiens, lipid envelope, glycoprotiens
2 types of virusus
dna and rna
RNA virus mechanisms (3)
- direct translation (gemone acts as mRNA) example: rubella
- viral rna transcribed by viral machinery (polyimerase) example: influenza
- rna reverse transcripted into DNA. example: HIV
DNA virus types
single strand or double strand, hijacks cells machinery or may have own to form viral dna (undergoes transcription to be Mrna and then forms viral protiens)
4 steps of virus infection and replication
- binding- to cell wall, endocytosed
- uncoating and replication - capsid shed, nucelic acod released. then replicated ( dna through cellular replication, rna through translation or reverse transcriptase)
- assembly
- release (through cell lysis makes non enveloped, through budding makes enveloped)
3 outcomes of viral infection
lytic- cell dies
latent- cell sits and waits
persistant- cell shed virus and survives but slowly releases viral components
where do dna vs rna virusu replicate
dna- nucleus
rna- cytoplasm
which type more sensitive to conditions
enveloped
example of enveloped and nonenveloped
enveloped- HIV
nonenveloped- polio
example dna vs rna
dna- herpes
rna- influenza
role of suracfe protiens (enveloped)
help with attachment and infection
