PSEUDOCOELOMATEPSEUDOCOELOMATEANIMALSANIMALS

General Zoology (Lecture)

BS BIOLOGY – 2October 9, 2012

PRESENTERS:

ALLAWAN, Jovany GleenCEDEÑO, Jekkey AnnDANLAG, Patrick JoelLUNA, NikkiSALAGA, HarveyTAGLUCOP, Marietta Ivana

I.I. BackgroundBackground

Pseudocoelamate - Greek word ‘Pseudo’ means

false, + ‘koil ma’ ṍ cavity.

Have a pseudocoelom

Composed of 7 phyla:

1. Rotifera 5. Nematomorpha

2. Kinorhyncha 6. Acanthocephala

3. Loricifera 7. Nematoda

4. Priapulida

IIII. . Evolutionary PerspectiveEvolutionary Perspective

Acoelomate

Lophotrochosozoa Ecdysozoa

Convergent Evolution

Aschelminthes

Pseudocoelomate (Morphology)

Disagreement among Zoologist

III. General CharacteristicsIII. General Characteristics

Body PlanBilateral symmetry

Germ layer: Ectoderm, Mesoderm, Endoderm (Triploblastic)

Unsegmented

Cylindrical in cross section

Pseudocoel

Size: Microscopic1um – 3 mm

Osmoregulation: presence of Protonephridia

Sex: Dioecious

IV. FORMS AND FUNCTIONSIV. FORMS AND FUNCTIONS

HabitatHabitat1. Cosmopolitan (anywhere in the world)

2. Freshwater- Rotifera

3. Marine- all except Nematomorpha,

Nematoda

4. Terrestrial- Rotifera, Kinorhyncha, Priapulida

LengthLength Phyla Length

Loricifera < 1 mm

Kinorhyncha < 1 mm

Rotifera 0.1 – 3 mm

Acanthocephala < 40 mm

Priapulida 2mm- 8cm

Nematomorpha 10 – 100 cm

Nematoda < 1mm-several meters

Length of Pseudocoelomate animalsLength of Pseudocoelomate animals

Integrated principles of Zoology, 11th edition by Hickman, Roberts, Larson

LocomotionLocomotion

1. Anchoring spines

2. Cilia

3. Contraction of Muscles

NutritionNutrition

• Digestive System - mouth, pharynx, intestine, anus

•Tegument- Acanthocephala

Growth and Development

•Larval Stage

Eutely

ExcretionExcretion

• Protonephridia -Except in Nematodes

Cloacal bladder

- Rotifera

Glandular and tubular system

- Nematoda

Unique characteristics

Nervous systemNervous system

Brain

Nerve Ganglion

SensorySensory

Eyespots

Amphids and Phasmids

ReproductionReproduction

• sexually and parthenogenesis

• Dioecious

V. CLASSIFICATION

Phyla

RotiferaClasses:

Seisonidea

Bdelloidea

Monogononta

Nematoda Classes:

Secernentea

Adenophorea

Kinorchyncha

Loricifera

Priapulida

Nematomorpha

Acanthocephala

VI. REPRESENTATIVE TYPES

Causes disease to humans1. Nematode

a. Ascaris lumbricoidesCommon name: Roundworm

b. Trichinella spiralisCommon name: Pork worm

c. Wuchereria bancroftiCommon name: Filarial worm filariasis

Ascaris lumbricoides

Hosts:Definitive- Humans

Life cycle

Harm- causes pneumonia and intestinal blockage

Ascaris worm in human intestine

Trichinella spiralisHosts:

Intermediate- PigDefinitive- Humans

Life Cycle

Harm: causes Trichinosis

Trichinella spiralis larvae in the muscle of the pig

Wuchereria bancroftiHosts:

Intermediate- mosquito Definitive- Humans

Life Cycle

Harm: causes elephantiasis

VII. Summary

Have a pseudocoel.

A constant number of body cells or nuclei (eutely).

Most have a complete digestive system with a well-developed pharynx.

composed of 7 phyla:

RotiferaClass:

Seisonidea Bdelloidea Monogononta

Nematoda Class:

Secernentea Adenophorea

Priapulida

Nematomorpha

Acanthocephala

Kinorhyncha

Loricifera

VIII. ReferencesZoology 7th ed. (S. Miller & J. Harley: ©2007)Zoology 8th ed. (S. Miller & J. Harley:©2011)Integrated Principles of Zoology 11th ed. (C.

Hickman, L. Roberts & A. Larson:©2001Integrated Principles of Zoology 14th ed. (C.

Hickman, L. Roberts & A. Larson:©2008http://msangellino.wordpress.com

/category/uncategorized/http://www.glerl.noaa.gov/seagrant/GLWL/Zooplankton/Rotifers/Pages/Asplanchnidae.html

THANK YOU FOR LISTENING AND GOD BLESS US ALL

Fig.1 Pseudocoelomate Body Plan

Fig.2 Triploblastic

Fig.4 Cylindrical in Cross Section

Fig.6 Tegument of Acanthocephala

Fig.7 Nerve Ganglion

Fig.8 Life Cycle of Ascaris lumbricoides

Fig. 9Life Cycle of Trichinella spiralis

Fig. 10 Life Cycle of Filarial worm

Fig. 11 Cylindrical in cross section

Fig.13 Protonephridia

Fig.15 Phasmids of Nematodes

Fig. 16 Amphids of Nematodes

Kinorhyncha Priapulida Loricifera

Digestive System of Rotifer and Nematode

MouthPharynx

Intestine

Anus

Contraction of Muscles

Fig.13 Protonephridia

Philodina Rotifer

Philodina Rotifer

Life Cycle of Acanthocephala

Locomotion of Rotifera

Brain of a Nematode

Parthenogenesis

Ovary

Spicules

Reproduction of Nematodes

Glandular and Tubular system of Nematode