Chapter 14: Class Cestoda Flashcards
Following the scolex there are a linear series of _________ or better known as _____. These are NOT considered true segments.
-reproductive units, proglottids.
Body type? Scolex?
- long flat bodies
- scolex is the head region…holdfast structure with suckers and hooks
They lack a_____system.
digestive
What systems are similar in this class to the others?
-muscular, excretory, and nervous sytems.
They lack sensory organs except for modified what?
cilia
The tegument is syncytical and has no what?
cilia
The entire surface of cestodes are covered with projects called ______ similar to microvilli seen in the vertebrate intestine. These do what for the organism?
- microtriches
- increase the surface area for food absorption
Subclass Eucestoda aka true tapeworms
- all have ____ and are ___
- larvae have six ____ on the scolex
- the chain of proglottids is called a _____
- proglottids originate in the germinative zone just behind the ___.
- Some practice this type of fertilization: __________ although the norm is ______.
- Shelled embryos form in the ____. Either expelled or the whole _____ is shed.
- Nearly all cestodes require two hosts. The adult is parasitic in the _____ of the vertebrate. Most tapeworms do little to no harm!
- proglottids, polyzoic
- hooks
- strobila
- scolex
- self-fertilization but norm is cross-fertilization
- uterus, proglottid
- digestive tract
Taenia saginata : Beef Tapeworm
- Lives as an adult in the alimentary canals of ___.
- Juvenile form found in the ______ tissue of cattle.
- Mature adults can reach over 10 meters in length with over 2000 proglottids. Scolex has four ____ but no hooks. Gravid Proglottids (with shelled, infective larvae) pass in ___.
- Excretory canals run from the scolex along the _____…flame cells attach to excretory ducts.
- Nerve cords from a nerve ring in the scolex run along the ____.
- Each mature proglottid has ____ and _____ plus ___ and ____ organs.
- Gravid proglottids usually ___ out of feces.
- Proglottids rupture as they ___. Embryos are viable for _____months.
- This order contains _____ in a single vitelline gland.
- humans
- intermuscular
- suckers
- feces
- proglottids
- proglottids
- muscles, parenchyma, male, female
- crawl
- dry
- 5
- vitellaria
Life Cycle of Beef Tapeworm?
- cattle swallow shelled larvae that hatch as ______.
- Oncospheres use hooks to burrow through the intestinal wall into ___ or ___ vessels.
- When they reach voluntary muscle, they ___ to become bladder worms aka _____.
- When infected meat is eaten, the cyst wall dissolves and the scolex _____ to attach to intestinal mucosa.
- New proglottids develop within??
- Infected individual expels numerous proglottids ___.
- Infection can BE AVOIDED via eating only?
- oncospheres
- blood or lymphs
- encyst, cysticerci
- envaginates
- 2-3 weeks
- daily
- thoroughly cooked beef
Taenia solium: Pork Tapeworm
- Adults live in the ______ of humans
- Juveniles live in ____ of pigs
- Scolex has both ____ and ____ on the rostellum
- If eggs or proglottids are ingested embryos migrate to organs and form ____.
- Cysticercosis occurs in ______ or the _____ blindness, serious neurological symptoms or even DEATH…
- Infection can be AVOIDED by eating ?
- intestine
- muscles
- hookers, suckers
- cysticerci
- eyes, brain
- thoroughly cooked pork
Diphyllobothrium latum: Fish Tapeworm
- Adults are found in the ___ of humans, dogs, cats and other mammals…
- Immature stages found in _____ and ____.
- Largest cestode of humans can reach ~____ metres
- intestine
- crustaceans, fish
- 20
Echinococcus granulosus
- adults parasitize ___ or other ____.
- juveniles infest many mammals.
- humans may serve as an _____ host
- Juveniles are a special cysticercus, a ____ cyst, that can grow for up to 20 YEARS. (harbours many future scolexs…larger reproduction)
- Main cyst maintains a single chamber, daughter cells bud off with thousands of ___ each able to produce a worm if eaten.
- Only one mode of treatment??
- dogs, canines
- intermediate
- hydatid
- scolices
- surgical removal
