Infectious Agents - SRS Flashcards
What infectious agents are visible at the E.M. level?
Prions
Viruses
What infectious agents are visible at the Micro level?
Bacteria
Fungi
Parasites
What infectious agents are visible at gross level?
Fungi
Parasites
How do prions replicate?
Misfolded protein causes misfolding of neighboring proteins
How do viruses replicate?
Nucleic acid replication using host mechanisms
How do bacteria reproduce?
Binary fission
How do fungi reproduce?
Asexual budding’
Sexual mating (spores)
How do parasites reproduce?
Sexual
Asexual
What kind of cell wall do viruses have?
What do some viruses have?
Protein capsid
Host cell envelope
What are some components of the fungi cell wall?
Chitin
Ergesterol
Gram + bacteria have an inner membrane and…
thick peptidoglycan
Gram (-) bacteria has inner and outer cell membranes and…
Middle thin peptidoglycan layer
What viruses are obligate intracellular?
All
What are some examples of obligate intracellular bacteria?
(6 were bolded in the chart)
- Clamydia,
- rickettsia,
- coxiella,
- erlichiae,
- anaplasma
- some mycobacteria (M. leprae)
2.
- some mycobacteria (M. leprae)
What is an example of an obligate intracellular fungi?
Pneumocystis
What are some examples of obligate intracellular parasites?
Plasmodia,
T. gondii,
C. parvum,
leishmania,
T. cruzi
(not bolded)
What domain do the following fall under?
Prions
Viruses
Bacteria
Fungi
Parasites
Prions - non-cellular
Viruses - non-cellular
Bacteria - bacteria
Fungi - eukaryota
Parasites - Eukaryota
Prions are not organisms but spread like an infectious agent, the misfolded protein causes misfolding of neighboring proteins. What isiform converts what normal protien into the infectious isoform?
PrPSc converts normal PrPC proteins into infectious isoform
When PrPSc converts normal PrPC proteins into infectious isoform, how do the abnormal proteins aggregate?
β-pleated sheet (amyloid)
Prions cause subacute (transmissable) spongioform encephalopathies. What are some example of this?
(4 bolded, 6 total)
- Kuru
- Creutzfeldt–Jakob disease
- Bovine spongioform encephalopathy - (variant Creutzfeldt–Jakob disease (vCJD))
- Scrapie
- Fatal familial insomnia
- Gerstmann-Straussler-Scheinker syndrome
How does one acquire Kuru?
Papua New Guinea via funerary cannibalism
How does one acquire Creutzfeldt–Jakob disease?
•human to human transmission via blood or tissue or inherited
What is variant Creutzfeldt–Jakob disease (vCJD)?
Bovine spongioform encephalopathy in humans
Where does Scrapie occur?
Prototype that occurs in sheep and goats
What are some normal flora of the skin?
- S. epidermides,
- S. aureus,
- corynebacteria,
- streptococci,
- propionobacteria,
- gram negative bacteria.
Name three normal flora of the nasopharynx.
S. aureus,
S. epidermides,
streptococci
What are some examples of oral cavity normal flora?
- streptococci,,
- neisseria,
- H. influenza,
- anaerobes (bacteriodes,prevotella, fusobacterium, actinomyces)
What are 4 example of normal vaginal flora?
- lactobacillus,
- streptococci,
- gram negative bacteria,
- candida
What are some normal flora of the colon?
- gram negative bacteria (E. coli),
- Enterococcus faecalis,
- anaerobes (bacteriodes, bifinobacterium, clostridium)
Why is hepatitis D an incomplete virus?
Does not have all the genetic material it needs for replication, needs some from another virus.
The major defense in skin is the epidermal barrier. What are four examples of how this barrier can fail?
- Mechanical defects (punctures, burns, ulcers)
- Needle sticks
- Arthropod and animal bites
- Direct penetration
What are the pathogens that take advantage of mechanical defects in the epidermal barrier (punctures, burns, ulcers)?
(3)
- S. aureus,
- Candida albicans,
- Pseudomonas aeuginosa
What is this sample of a prion disease referred to?
Bubbly looking things in cells cause tissue to look like a sponge.
Thus called spongioform encephalopathies
What are two common needle stick pathogens?
HIV
Hepatitis Virus