PLATYHELMINTHES Flashcards
What type of symmetry?
bilateral
diploblastic or triploblastic?
triploblastic
acoelomate, coelomate, or no coelom?
acoelomate
What type of body cavity?
Gastrovascular cavity
What order?
* Gut with three branches
* Marine, freshwater, and terrestrial
Order Tricladida
What order?
* Gut with many branches
* Large marine flatworms
* Often brightly colored
Order Polycladida
What group?
* Monogenetic flukes
* Most are ectoparasites
* Hooks on both ends to attach to host
Monogenea
What group?
* Digenetic flukes
* Most are endoparasites
* Suckers to attach to hosts
Trematoda
Digenea
What group?
* Tapeworms
* Endoparasites
* No digestive tract
Cestoda
Explain nervous system
Head region with a cerebral ganglion and sense organs (tactile, chemical, water flow, light, orientation)
Explain reproductive system
Elaborate reproductive systems
* Simultaneous hermaphrodites
How do they osmoregulate?
Protonephridia for osmoregulation in freshwater species
What type of muscular system?
Muscular antagonistic
system
What is the function of Rhabdoids?
Rhabdoids produce mucus and noxious compounds
How do they support themselves?
Hydrostatic mesenchyme and muscular antagonistic system
How do they move?
Crawl using cilia and mucus secretion
How do they feed themselves?
Carnivorous or scavengers
* Three types of pharynx
Explain modes of asexual reproduction
- Transverse fission
- Able to regenerate lost body parts
- Totipotent cells called neoblasts
What type of cleavage?
spiral
What type of blastula?
stereoblastula
What type of development?
determinate development
Monogenea and Trematoda:
what is the function of the tegument?
Tegument provides protection and aids in gas exchange.
Monogenea and Trematoda:
Ciliated or no cilia?
no cilia
Monogenea and Trematoda:
How do they move?
using muscular action
Monogenea and Trematoda:
How do they adhere?
Monogenetic flukes have
attachment organs at both ends.
Prohaptor at oral end with
suckers, opisthaptor at hind end
with barbed suckers.
Digenetic flukes have an oral
sucker at oral end and an
acetabulum on ventral surface.
Monogenea and Trematoda:
How do they feed?
Feed on host tissues by pumping of muscular pharynx.
Gut with two cecae lined with cells for nutrient uptake.
Monogenea and Trematoda:
How do they reproduce and develop?
Simultaneous hermaphrodites with mutual cross fertilization.
Eggs are ectolecithal and can be brooded for long time.
Indirect development with one or more free living larval stages.
How many hosts for a monogenetic fluke?
One
How many hosts for a digenetic fluke?
more than one
What is the name of an individual Cestoda segment?
proglottids
Cestoda:
How do they feed themselves?
No gut. Nutrient uptake (both
pinocytosis and diffusion) across
tegument with microtriches.
