Cestodes Flashcards
What are cestodes referred to as
Tapeworm
What phylum and class are cestodes in
Phylum platyhelminth, class Cestoda
Describe the general shape of cestodes
Flattened dorsal ventrally, ribbonlike and segmented, containing segments called proglottids
Describe the morphology of eucestodes
Has a scolex at the anterior end. Some have acetabula and Rostellum
What is a scolex
A head
What is a acetabula
Suckers
What is a Rostellum
Spiky head
If a cestode has a Rostellum what do you consider him
Armed
If I cestode does not have a rostellum what do you consider him
Unarmed
What is very special about eucestodes and how they intake food
They have no digestive track. They intake their food through the skin
What can we say about the proglottids that are close to the scolex
They are young proglottids
What can we say about the proglottids that are mid-distance from scolex
They are more mature
What can we say about the proglottids that are furthest from the scolex
They’re mature and gravid
What is cross fertilization when it comes to eucestodes
One proglottid fertilizes with another proglottid
What is self fertilization when it comes to proglottids
They fertilize themselves
What is special about eucestodes in terms of sexual reproduction
They are hermaphroditic.
What can be said about a gravid proglottid and it’s reproductive organs
The reproductive organs have degenerated and only the uterus remains with the eggs inside
Describe a proglottid egg
It is a six hooked hexacanth. It is born with all of its hooks already
Describe to eucestode life cycle
Gravid proglottids are expelled. Proglottids rupture and release eggs. Ingested by an obligate intermediate host where it develops into a metacestode (6 different forms possible)
What happens if a eucestode is eaten by a flea
It becomes a cysticercoid
What happens if the eucestode is eaten by a mama
Becomes a cysticercus, coenurus, hydatid cyst
Where do eucestodes live
In the digestive tract
How do definitive host become infected with eucestodes
It’s the intermediate host at the metacestode stage
What is the definitive host for taenia saginata
Human
What is the intermediate host of Taenia saginata
Cattle