P H Y L U M N E M A T O DA

1. P H Y L U M N E M A T O DA ISABELLA DAO THONG NGUYEN PERIOD 6

2. G E N E R A L C H A R A C T E R I S T I C S • Nematodes are commonly called roundworms. • Nematodes are called so because “nematos,” in Greek, means thread. • Not many species of nematodes are named, but it is estimated that there are around half a million species. • They are unsegmented and can be microscopic to a meter long. • Most nematodes are free-living, dwelling in between spaces of soils and sediments.

3. C L A S S E S O F P H Y L U M N E M A T O D A • Class Secernentea • Pore-like or slit-like amphid apertures, always labial • Excretory system tubular • Male generally with a single testis • Sensory papillae cephalic only, although may be caudal papillae in males • Esophagus varies but has 3 esophageal glands • Almost exclusively terrestrial, rarely freshwater or marine • Class Adenophorea • Unsegmented worms • Simple non-tubular excretory • system when present • Male generally has two testes • Sensory papillae in cephalic region and along the body • Generally there are five esophageal glands • Marine, freshwater, terrestrial

4. CLASS SECERNENTEA A S C A R I S – Common Round Worm T R I C H U R I S – Hook Worm http://www.e-cleansing.com/common-roundworm-ascaris-lumbricoides-2/ http://www.britannica.com/EBchecked/topic-art/461262/6935/Pinworm http://www.smittskyddsinstitutet.se/upload/Analyser-tv%C3%A5/ CLASS ADENOPHOREA E N T E R O B I U S – Pin Worm

5. Bilaterally symmetrical- it takes 1 plane to divide the organism into mirror image halves. • Vermiform- resembling a worm; worm-shaped; long, slender, and cylindrical. BODY PLAN http://www.fauna.is/photos/II020hringormur.jpg http://tolweb.org/tree/ToLimages/PHIL_1448_lores1.250a.jpg These nematodes are mirror image halves on both sides.

6. F E E D I NG • Nematodes feed on about everything. • Habitat and way of life determines feeding method utilized. Therefore, Nematodes have a wide range of feeding habits: carnivorous, herbivorous, and parasitic. • Have complete digestive system with mouth and anus • Nematodes do not have stomachs, only intestines. http://www.berkley.k12.mi.us/file_repository/id152709nemata.ppt#263,8,How do nematodes circulate nutrients and osmoregulate?

7. F E E D I N G C O N T. • The mouth of a nematode opens to a muscular pharynx. This pharynx pumps food from the mouth to the intestine http://soils.usda.gov/sqi/concepts/soil_biology/nematodes.html • Digestive enzymes are produced by a single layer of epithelial cells lining the intestines. • Digestion first occurs first in the intestinal lumen (space inside the intestines). Digestion is completed intracellularly. • Nutrients and wastes are distributed in the body cavity.

8. F E E D I N G C O N T. • Picture of a male nematode (Use this diagram for reference when looking at parts of nematodes). http://www.sci.sdsu.edu/classes/bio201/NEMATODA%20B.GIF

9. F E E D I N G C O N T. • Nematodes can parasitize plants, animals, and humans. They are virtually parasitic to every type of animal and plants. http://www.bioraynaturaldetox.com/uploads/images/roundworm.jpg Round worms (Ascaris Lumbricoides) in the human intestine. 

10. R E S P I R A T I O N • Nematodes do not have respiratory systems. • They obtain oxygen by diffusion from the surrounding environment through the cuticle.  (right) Sediments with crevices in which Anatartic nematodes live. http://static.radionz.net.nz/assets/image/0007/1660084/varieties/443_full_width.jpg

11. Nematodes do not have circulatory systems. • Circulation occurs through the movement of fluids back and forth in the pseudocoelom. CIRCULATION

12. E X C R E T I O N • Excretion of metabolic waste (ammonia/urea) via diffusion across body walls • No formal internal transport system • Excretory canals located on both sides of the intestine facilitate waste disposal by carriage of material to an excretory pore in the body wall. http://www.cartage.org.lb/en/themes/sciences/zoology/biologicaldiverstity/AnimalsI/AnimalsI.htm

13. Simple nervous system consisting of several ganglia • They have a ring of amphids and phasmids (somewhat complex sense organs) that surround anterior and posterior end, respectively • Four primary nerves run the length of the body on the dorsal, ventral, and lateral surfaces • Body of nematodes are covered in sensory bristles and papillae that provide sense of touch R E S P O N S E

14. M O V E M E N T • No circular muscle in body walls • Longitudinal muscle flexion combined with high internal fluid pressure produces whip-like wriggle • Each muscle cell has a contractile fibrillar portion and a noncontractile sarcoplasmic portion • Pseudoceolom and outer cuticle provide “hydroskeleton” for movement http://www.berkley.k12.mi.us/file_repository/id152709nemata.ppt#260,5,How do nematodes support themselves and move?

15. Sexual reproduction with sexes separate (dioecious) • Internal fertilization • Zygotes covered in shells and directly deposited • Males usually smaller than females • Both sexes possess one or two tubular gonads (organs that produce gametes, i.e. testes and ovaries) http://www.protocol-online.org/biology-forums/posts/25467.html R E P R O D U C T I O N

16. W O R K C I T E D Ascaris. Digital image. Web. 16 Apr. 2010. <http://www.e-cleansing.com/common-roundworm-ascaris-lumbricoides-2/>. "Ascaris Lumbricoides: EMedicine Emergency Medicine." EMedicine - Medical Reference. Web. 16 Apr. 2010. <http://emedicine.medscape.com/article/788398-overview>. "Bilaterally Symmetrical Definition." Department of Biochemistry, Molecular Biology, and Cell Biology - Weinberg College of Arts and Sciences - Northwestern University. Web. 16 Apr. 2010. <http://www.biochem.northwestern.edu/holmgren/Glossary/Definitio ns/Def- B/bilaterally_symmetrical.html>. Circular Nematode. Digital image. Web. 16 Apr. 2010. <http://www.fauna.is/picture2e.asp?ID=1387>. Dictionary.com. Web. 16 Apr. 2010. <http://dictionary.reference.com/browse/vermiform>. Enterobius. Digital image. Web. 17 Apr. 2010. <http://www.britannica.com/EBchecked/topic-art/461262/6935/Pinworm>. "Flukes." Biology Program at ISU. Web. 16 Apr. 2010. <http://www.biology.iastate.edu/Courses/211L/Nemato/Ascarindx.ht m>. "Introduction to the Nematoda." UCMP - University of California Museum of Paleontology. Web. 17 Apr. 2010. <http://www.ucmp.berkeley.edu/phyla/ecdysozoa/nematoda.html>. Nematode diagram. Digital image. Web. 16 Apr. 2010. <http://www.sci.sdsu.edu/classes/bio201/Nematodes.html>. Nematode Excretion. Digital image. Web. 16 Apr. 2010. <http://www.cartage.org.lb/en/themes/sciences/zoology/biologicaldiverstity/AnimalsI/AnimalsI.htm>. Nematode feeding. Digital image. Web. 18 Apr. 2010. <http://soils.usda.gov/sqi/concepts/soil_biology/nematodes.html>. Nematode movement. Digital image. Web. 17 Apr. 2010. <http://www.berkley.k12.mi.us/file_repository/id152709nemata.ppt# 260,5,Howdo nematodes support themselves and move?>. Nematode Reproduction. Digital image. Web. 17 Apr. 2010. <http://www.protocol-online.org/biology- forums/posts/25467.html>. Nematode worm. Digital image. Web. 16 Apr. 2010. <http://tolweb.org/Nematoda/2472>. "The Nematodes (Phylum Nematoda)." The Earth Life Web. Web. 16 Apr. 2010. <http://www.earthlife.net/inverts/nematoda.html>. Photographs. Deviant Art. Web. 18 Apr. 2010. <http://www.deviantart.com>. Photographs. Flickr. Flickr. Web. 18 Apr. 2010. <http://www.flickr.com>. "Radio New Zealand National : Programmes A-Z : Our Changing World : 20080717." Radio New Zealand. Web. 16 Apr. 2010. <http://www.radionz.co.nz/national/programmes/ourchangingworld/20080717>. Round Worm - Ascaris. Digital image. Web. 17 Apr. 2010. <http://www.bioraynaturaldetox.com/where-do-i-start/parasite- cleanse.aspx>. Trichuris. Digital image. Web. 17 Apr. 2010. <http://www.smittskyddsinstitutet.se/upload/Analyser-tv%C3%A5/>.