Parasite Life Cycles Flashcards
What do life cycles show?
Series of developmental events, including growth and reproduction
-it major life event
Direct Lifecycles (monoxenous)
-Only require one host
-Can reinfect the same host in which sexual reproduction occured
Round Worm (Ascaris Lumbricoides)
Direct Lifecycle
-Eggs with larva in it
-Humans ingest eggs and go to intestine
-The hatched larva enter circulation and migrate to the lungs where they are coughed up and enter the digestive tract
-Mature in the small intestine
-Egg pooped out
Pin Worm
Direct Lifecycle
-Egg ingested by human
-Goes to intestine
-Hatch in small intestine
-Female with fertilized eggs moves to the anus and glue eggs to the anal folds
-It really itch so kids will itch and then touch things that put the eggs on other things
Giardia
Direct Lifecycle
-A cyst contamination in water
-Human drinks water
-In intestine the giardia divides and divides forming back into a cyst
-Gets passed in stool
Entamoeba
Direct Lifecycle
-Cysts ingested
-Hatch in digestive tract
-Multiply but get back to cysts form
-Passed in feces
Indirect Lifecycle (heteroxenous)
-Require two or more hosts
-A definitive host where sexual reproduction will occur
-Intermediate host where larval development occurs
If asexual reproduction happens is that the direct host?
No, that is still the intermediate host
Phylum Acanthocephala
Indirect Lifecycle
-Consumption by definitive host (Lizard)
-Eggs passed in feces
-Eggs consumed by arthropod
-Eggs hatch in gut
-Formation of cystacanth
Alaria Americana (Fluke)
Indirect Lifecycle
-Sexual reproduction in definitive host (fox)
-Eggs released in feces
-Miracidium hatches
-Asexual reproduction in first intermediated host (snail)
-Cercariae released and penetrates the second intermediate host (tadpole)
-Tadpole can be eaten by fox or it can get eaten by a paratenic host
-Paratenic host the parasite does not develop and wait to be consumed by the fox
Digenetic Trematode
Alternate between a vertebrate host and a snail host
