Medical Parasitology Lecture 3 - Life Cycle of Cestodes (Flashcards)

Flashcards to review the Cestodes lecture.

Cestodes have a flat, ribbon-like body with an anterior attachment organ called a __.

scolex

The body of a cestode is called the __ and consists of a chain of segments called proglottids.

strobila

The __ of a cestode is characterized by the presence of sucking discs or lateral grooves.

scolex

Some cestodes have hooks on a small button-like structure on the scolex called the __.

rostellum

New proglottids bud from behind the __ in cestodes.

scolex

Proglottids filled with eggs are called __ proglottids.

gravid

__ embryos (onchospheres) develop within the eggs of cestodes.

Hexacanth

The __ is a relatively differentiated zone between the scolex and the strobila.

neck

Cestodes complete their life cycle in __ different hosts (with one exception).

two

The larval tapeworm in intermediate hosts is called __.

metacestode

__ is the process within the egg that results in a larva (oncosphere).

Embryogenesis

The oncosphere penetrates to a __ site after being eaten by the next host.

parenteral (extraintestinal)

The metamorphosis of the larva in the parenteral site results in a juvenile __ usually with a scolex.

metacestode

Four medically important cestodes are Taenia solium, Taenia saginata, Diphyllobothrium latum, and __.

Echinococcus granulosus

Other cestodes of lesser medical importance include Echinococcus multilocularis and __.

Vampirolepis nana

__ is the only cestode for which man acts as both the definitive and intermediate host.

T. solium

The chain of proglottids in Taenia spp. is called the __.

strobila

Cysticercus __ is the larva of T. solium.

cellulosae

T. solium adult worms may cause mild irritation or inflammation of the intestinal mucosa due to their __.

armed scolex

Taenia spp. eggs contain a __ embryo (oncosphere) with 6 hooklets.

hexacanth

The definitive host for Taenia saginata is __.

human being

The discharged stage of Taenia spp. is __ or gravid proglottids in feces.

eggs

The intermediate host for Taenia saginata is __.

cattle

The intermediate host for Taenia solium is __.

swine

Infection by eating cysticercus results in __.

Taeniasis

Intrinsic or extrinsic auto-infection due to T. solium egg only results in __.

cysticercosis

Taenia spp. eggs __ be speciated through faecal exam.

cannot

__ is used for the treatment of Taeniasis.

Praziquantel

Diphyllobothrium latum is also known as the __ tapeworm.

broad fish

The infective stage for mammals in Diphyllobothrium latum is the __ larva.

plerocercoid

The scolex of Diphyllobothrium latum has a pair of suctorial grooves known as __.

bothria

The egg of Diphyllobothrium latum exhibits an __.

operculum

__ is used to treat infection by Diphyllobothrium latum.

Niclosamide

__ is a disease caused by Echinococcus granulosis.

Hydatidosis

Adult Echinococcus granulosis worms are only found in __.

canines

Humans accidentally ingest __ (infective stage) of Echinococcus granulosis from close contact with an infected animal or from canine faeces.

eggs

The hexacanth develops into the __ stage (hydatid cyst) in tissues.

larval

The scolex of Echinococcus granulosus has 4 suckers and is armed with __ hooklets.

28-48

The adult worm of Echinococcus granulosus consists of only __segments.

3

__ of tissue can result from larger cysts of Echinococcus granulosus.

Pressure necrosis

__ removal of cyst is a treatment for Hydatidosis.

Surgical

__ is a drug used against hydatid cysts.

Albendazole, mebendazole and praziquantel

__ tapeworm do not require intermediate host to infect humans.

Dwarf

In Vampirolepis nana, the __ stage is egg or insects containing the larvae.

infective

__ - infected humans can ingest eggs from their own faeces, an infection method for Dwarf tapeworm.

Autoinfection

Dwarf tapeworm scolex has 4 sucking disks and short rostellum with __.

hooks

Dwarf tapeworm __ are broader than long; rarely seen in faeces specimens.

proglottid

Dwarf tapworm __ are most often seen stage in specimens.

eggs

Good __ hygiene is a prevention method for Dwarf tapeworm infection.

personal

__ is one of the treatment drugs for Dwarf tapeworm

Niclosamide