Transcript Platyhelminthes

Protosome-Protozoa
Domain: Eukaryotic Kingdom: Animalia
Phylum: Platyhelminthes
Inside
 No circulatory system
 A. Diffusion
 No Respiratory organs
 A. Diffusion for respiration
 1. Makes them vulnerable to
fluid loss, therefore live in
water
 No anus
 A. Regurgitate undigested material
through the gastrovascular cavity,
pharynx, and mouth
 Nervous system
 A. Simple brain
 1. Ganglion-simple bundles of
nerves
 ventral nerve cord-run down
each side of flatworm
Outside
 Multicellular
 Bilaterally symmetrical
 Unsegmented
 Flattened
 Soft Bodies
 Asexual
 Transversal Bipartition
 regenerate their tissues
 Sexual
 Hermaphrodites
 Have both male and
female parts
 Subgroups
 Turbellaria
 Largest of the three
 Monogenea
 No more than two cm in
length
 Trematoda
 No more than two cm in
length
 Examples
 Tapeworms
 Planaria
 Flukes
Parasitic
Free living
 Monogenea, and
 Turbullerians
Trematoda
 Feed off of a host
 Infect blood and organs of
host
 Capture Prey
 Most are carnivores
 Have a pharynx that
pumps food into
 Including humans
gastrointestinal cavity
 Have a pharynx that pumps  Heterotrophs
food into gastrointestinal
 Prey on:
cavity
 annelids, arthropods,
 Heterotrophs
mollusks, and tunicates
 No internal cavity
Cnidarians and
Ctenophores
 Acoemorphic
 Organs have direct
contact with the
epithelium
Platyhelminthes
More "advanced"
bilaterians
Bilateral symmetry
No
Yes
Number of main
cell layers
Two, with jelly-like
layer between them
Three
Distinct brain
No
Yes
Digestive system
No
Yes
Specialized
excretory system
No
Yes
Body cavity
containing internal
organs
No
Yes
Specialized
circulatory and
respiratory organs
No
Yes
Protosome-Ecdsozoa
Domain: Eukaryotic Kingdom: Animalia
Phylum: Nematoda
 Inside
 Outside
 No circulatory system
 diffusion
 Nitrogenous waste excretes
through body wall
 form of ammonia
 no specific organs
 Four peripheral nerves
 Run the length of the body
 Ventral nerve -largest
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Combines both sensory and motor
 Dorsal nerve -motor control
 Lateral nerves-sensory
 Smaller nerves -supply the sensory
organs of the head
 Reproductive system
 Have distinct males and females
 Males find females and mate
 Males are usually smaller than
females
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Multicellular
Cylindrical
Bilateral Symmetry
Head is radially symmetrical
 sensory bristles
 Adhesive 'caudal gland'
 found at the tip of the tail
 Subgroups
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Class Dorylaimea
Class Enoplea
Class Secernentea
Subclass Diplogasteria
Subclass Rhabditia
Subclass Spiruria
Subclass Tylenchia
"Chromadorea“
*Examples
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Vinegar eels
Caenorhabditis elegans
Toxocara canis
Hookworms
Parasitic
Free living
 Oral cavity with cuticle
 Oral cavity
 Four molts of the cuticle
 Play important role in the
 Hookworms, Pinworms,
Whipworms
 Feed mostly on humans
and household animals
 Trichina worm
 Feed on rats, pigs and
other animals
decomposition process
 Feed on:
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Algae
fungi
small animals
fecal matter
dead organisms
living tissues.
 Thick cuticle that covers
body
 Above epidermis layer
 can be shed for growth
 two or three distinct
layers
Angelicka^2
http://en.wikipedia.org/wiki/Nematode#Reproduction
http://en.wikipedia.org/wiki/Flatworm
http://www.wetwebmedia.com/f latworms.htm