What parasites do pt.2 Flashcards
Example Migration within a host
Example: Ascaris suum
Eggs get eaten by pig then goes to intestine where is enter circulatory system comes back to lungs gets coughed up to go back to digestive tract to be pooped out
Why would parasites migrate once already in a host
There a a few theories,
1) A. suum has evolved from a different species that need an indirect lifecycle but this one does not and just kept this lifecycle trait
2) Worms migrating possible grow faster, large- but this does not seem as likely because migration is very dangerous even being inside a host
What happens if a parasite enters an inappropriate host?
Aberant migration occurs
Wander through the skin leaving trail of inflammation called
cutaneous larval migrans
due to penetration human skin and not being able to get passed the basal layer of skin
What are things parasites have deal with to maintain position?
Peristalsis
Rushing blood
Environmental factor and grooming behaviors
Adhesive disk
Disk creates suction to resist flow of intestinal contents
Example of adhesive disk
Giardia lamblia
Hooked structures
The head imbeds into the intestinal wall while the tail floats behind
Example of hooked strucutres
taenia solium (pork tapeworm)
Acanthocephala (thorny-headed worms)
Sinusoidal Motion
sinusoidal motion to offset peristaltic movements of host
Example of sinusoidal movements
Ascaris lumbricoides (human roundworm)
Acetabula
Flukes suckers that attach to target tissue
Membrane proteins
PfEMP1 protein to adhere to blood vessels, to avoid clearance by the spleen
Example of membrane proteins
Plasmodium falciparum (malaria)
Morphology
Ectoparasites have structures that help them stay on host
