1. Nematoda and platyhelminthes are two phyla of worms. Nematoda includes roundworms and threadworms, many of which are parasites. Platyhelminthes includes flatworms like flukes and tapeworms. 2. Nematodes have slender cylindrical bodies and no internal segmentation. They are found abundantly in soil and water. Platyhelminthes are soft-bodied and either leaf-like or ribbon-like in structure. 3. Both phyla include many parasitic species that can cause diseases in humans and other animals. They also play important ecological roles in soil, water, and as parasites within other species.

1. Nematoda & platyhelminthes
Presented by:
Shahadat
Hossain(ASH1819043M)
Nusrat jahan(MUH1819039F)
Arnima Aich(BKH1819014F)
Shatabdi Dhar Bithi
(BKH1819019F)

2. Nematoda
• A large phylum of worms with
slender, unsegmented,
cylindrical bodies, including the
roundworms, threadworms and
eelworms. They are found
abundantly in soil and water,
and many are parasites.

3. Special Features Of Nematode
• Invertebrates
• The body is covered by a catalyst
• Body is the body cavity of the Pseudocael
• They are tristari animals
• Their body does not have round muscles
• Most of them are single handed
• Most species live in parasitic plants and animals and some species live
in sweet water as an independent
• Their inner muscles are present in fixed number cells

4. Classification Of Nematoda
1. Adenophora or Aphasmida
• Example: Trichinella Spirals
2. Secernetea or phasmidea
• Example: Ascaris lumbricodes

5. Structure Of Nematoda(Ascaris lumbricoides)

6. Life cycle of nematoda

7. Importance Of Nematoda
Advantages
• Important part of microbial food
webs in soil and water.
• some are used as biological agents.
• yield losses of up 87% have been
reported (lilley at al 2011)
• Losses of potatoes due to
Meloidogyne species are
estimated at 25% or more
• Disadvantage
• Nematodes ars microscopic
roundworms that damage plant
tissues as they feed.
• Harmful parasite of mushrooms.
• Nematodes have also been
reported to transmit fungal
pathogens.
• Nematodes cause several diseases.
Such as- Trichinosis, Hookworms,
Pinworms, Heatworms.

8. Disadvantage Of Nematode

10. What is Platyhelminthes
• The name of the phylum derives
from the Greek platy meaning
"flat" and helminth meaning
"worm".
• Members of this Phylum are
soft,thin-bodied,leaf or ribbon
like worms,the flukes and
tapeworms parasitic in human
and other animal bodies

11. General Characteristics
• Body Symmetry:
• Bilateral-Mirrored right and left sides.
• Body Organization:Triploblastic
• Epiderm(outside)
• Mesoderm(middle)
• Endoderm(inside).
• Body cavity:Acoelomate
• Digestive system:Mouth and gastrovascular cavity.
• Circulation :Diffusion

12. Characteristic
• Reproduction : 2 types.Sexual and Asexual.
• Sexual :Hermaphroditic-cross fertilization between 2 worms.
• Asexual:Fragmentation.
• Respiration :Diffusion through skin.
• Excretion:Tubes open to outside,flame cells and mouth.
• Habitat:Host and freshwater.

13. Classification Of Plathyhelminths
Class-1
Turbellaria
• Usually non-parasitic,free
living worms are called
planarians.
• Mostly hermaphrodic,some
reproduce asexually.
Example- Convoluta,Afronta.

14. Class 2
Trematoda
• Ecto or endo parasitic flatworms
called flukes.
• Suckers and sometimes hook
present.
• Example :Diplozoom,Polystoma.

15. Class-3:
Cestoda
Endoparasitic flatworms,called
tapeworms.Body
segmented..Scolex (head) with
suckers,or hooks,or both
Ex- Amphilina,Ophiotaenia

16. Life cycle of Fasciola hepatica

18. Economic Importance of platyhelminths
• Positive impact:
• 1.flatworms play important role in marine,fresh water and terrestrial
of ecosystems
• 2.Flatworms have been part of important role in biological
communities.
• 3.Flateworms absorb all oxygen via diffusion from the surrounding air.

19. • Negative Impact:

20. Reference
Animal Diversity-l (kabir Publication)
Invertibrates-(R.L.Kotpal)
 www.wikipedia.org
www.ucmp.berkeley.edu
 www.animaldiversity.org
 www.untamedscience.com