eLA: Microbes and Diseases Flashcards
What are prions?
Prions are infectious proteins and the smallest infections agent. A prion is a rogue abnormally folded cellular protein that will induce a normal fold protein to misfold as well.
What are viruses?
An aceullar infectious agent that relies on machincery of a host cell to replicate. Lysogeny is wehn the virus integrates its genome into the host cell genome.
The lytic phase is the active phase of the virus and intiates symptoms in the host.
- cellular immunity to deal with virus inside the cell
- humoral immunity to deal with virus during extracellular stage.
What color is gram postivive bacteria stain? What do they have?
Staines red, have a thick peptidoglycan cell wall suroruouning one lipid bilayer membrane.
What color do gram negative bacteria stain and what do they have?
Gram negative stain purple and have a thin cell wall betweeen two membranes. The surface is covered in Lipopolysaccaride or LPS also called endotoxin
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What is commensal
microorganism is symbiotic relationship with hose
what is virulence?
The degree of pathogenicity
What are the stage of infectios disease?
- Incubation period (from acquiristion to diease onset)
- Prodome (nonspecific symptoms)
- Spcific illness (localized or systemic)
Convalescence (after resolution of symptoms to complete recover)
What pathogens are dangerous for crossing the placenta?
Listeria, and syphillis (caused by T. Pallidum)
Describe the normal flora
- gram positive colonize the skin
- sterile parts (no flora so bad if bacteria gets there) are lung, cerebrospinal space, GI tract upward from the bladder
What do virulence factors do?
Help bacteria to invade the host, cause disease, and evade host defenses
WHat is biofilm?
Biofilm is bacterial polysaccharides that allow bacteria to stick to each other and attach to a sruface like plauqe on teeth. is is a type of adhesion.
What are invasins?
Some bacteria travel to the host cell interior by hitchhiking the phagocytic pathway. Other take a more ative rule by using invasins to hijack a similar cellular mechanism. Invasins are surface proteins that mediate uptake of the bacteria into normally non-phagocytic cells, allowing them to esacep the humoral immune response.
WHat is transcytosis?
Bacteria polymerizes host actin at one pull and pushes itself through the cell into a neighboring cell without exiting into the hostile environemtn filled with antibodies
What is antigenic variation?
Process that bacteria use to swtich the antigen rendering the previous antibodies useless. Allows for persiten infection.
What is Hemolysin?
Process Bacteria use to lyse RBCs in order to use their iron
