Unit 2 - Principles of immunology Flashcards
describe the metabolism of bacteria
facultative: anaerobic - does not have detoxification enzymes - slower process - yields 47 kCal/ aerobic - yields 487 kCal
describe the two types of bacteria according to their cell wall
gram positive -thick wall of peptidoglycan - stains purple
gram negative - double membrane - peptidoglycan and lipopolysaccharide - negative charge - does not stain but with counter stain - pink
how can bacteria be identified?
- colony morphology - coccus (round)/ bacillus (rod)/ spirillus/ spirochaetes (helix)
- microscopy
- substances produced
- growth requirement
describe properties of fungi
- eukaryotic in nature
- unicellular or multicellular
- molds form mycelia - hyphae
- cell wall made of chitin
what type of infection do fungi form?
- superficial
- systemic
how are protozoa classified?
according to locomotion = appendages/ pseudopodia (amoeba)
describe properties of protozoa
- eukaryotic
- unicellular
- free living or parasite
- absorb nutrients from environment
describe helminths
multicellular parasites
round worms and flat worms
what are prions?
misfolded proteins causes TSE (transmissible spongiform encephalopathies) - rare progressive neurodegenerative disorders
describe the structure of viruses
capsomeres - capsids
envelope
contain either RNA or DNA
how are viruses detected?
serology - antibodies
microscopy
culture
PCR
describe the life cycle of a virus
entry- uncoating -replication - protein synthesis - assembly - release
describe types of viral infections
acute/ lytic
chronic
latent/ proviral
transformation
what is the baltimore classification of viruses?
classification based on nucleic genomes
(+) = sense - used as mRNA directly for translation
(-) = anti-sense - have to produce mRNA
1. dsDNA (herpes)2. ssDNA (adenovirus) 3. dsRNA (neovirus) 4. (+)ssRNA (polio/ hep A/ hep C) 5. (-) ssRNA (influenza) 6. reverse RNA (HIV) 7. reverse DNA (hep B)
what are the two types of infections?
endogenous - self-infection
exogenous - person to person transmission/ environmental/ HCA
what are virulence factors?
pathogenesis
- adhesion
- capsule
- resistance to serum
- biofilm
- motility