Chpt 7 - The Phylum Platyhelminthes, Class Trematoda Flashcards Preview

Parasitology > Chpt 7 - The Phylum Platyhelminthes, Class Trematoda > Flashcards

Flashcards in Chpt 7 - The Phylum Platyhelminthes, Class Trematoda Deck (12):
1

Monogenetic trematode

Ectoparasite of fish, amphibians, and reptiles

2

Acetabulum

Ventral sucker that is used as a "holdfast" organ of attachment for digenetic flukes

3

Miracidium

Motile stage emerging from operculated fluke egg

4

Sporocyst

Developmental stage following penetration of the miracidium into snail (first intermediate host)

5

Redia

Stage that develops on the inside of the sporocyst

6

Cercaria

Stage that follows the redia; stage that emerges from the second intermediate host

7

Operculum

"Door" or cap at one end or pole of the trematode egg

8

Hermaphroditic

Simultaneously possessing both male and female reproductive organs

9

Metacercaria

Encysted stage in the life cycle of the trematode usually found on vegetation or within second intermediate host

10

Digenetic trematodes

Endoparasitic flukes of both domestic and wild animals

11

How are monogenetic trematodes different from digenetic trematodes?

Monogenetics are ectoparasites of fish, amphibians, and reptiles; digenetics are endoparasites of both domestic and wild animals.

12

Developmental stages in life cycle of digenetic fluke

*Operculated egg contains a ciliated miracidium
*Developed eggs are deposited in water
*Miracidium hatches from egg, swims around and penetrates aquatic snal
*Miracidium forms sporocysts in snail
*Sporocysts then produce several rediae
*Each redia then forms several cercariae (cercariae are motile tadpole like life stages with single or forked tail)
*Cercariae then leave snail, swim in water and depending on species take one of the following paths:
1. Directly penetrate DH and mature
2. Form a cyst (metacercaria) on plants, which will be ingested by DH
3. Penetrate 2nd IH, form a cyst (metacercaria) and will then - together with the IH - be ingested by DH