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Aims of the CourseOverall aims:

Recognizing the diversity of God’s creation of different coelomic invertebrates animalsDeveloping the familiarity with the coelomic invertebrate phylaAcquisition of facts and concepts on the biology, body organs and their function of invertebrate animalRecognizing of the importance of this course and other scientific courses taught in this programIncreasing the teamwork skills and using of internet and microscopes

Intended learning Outcomes (ILO’s)Knowledge and Understanding

oRecognizing the most major coelomic invertebrate phylaoUnderstanding the biology and internal organs and their function in the different invertebrate animalsoUnderstanding the taxonomic classification and evolutionary position of the different phyla

Intellectual SkillsoComparing between the taxonomic criteria and organs throughout the different invertebrate animals

Professional and Practical SkillsoExamining the animals using the microscope and drawing their organs to recognize the taxonomic criteria

General and transferable SkillsoLearning the participating with student colleaguesoLoving the scientific courses felt their utility in public lifeoParticipating in gaining information from the internet 2

SyllabusSyllabus•Introduction

•Phylum: Annelida (General charactes)

•Nereis

•Allolobophra caliginosa

•Hirudo medicinalis

•Phylum: Arthropoda (General charactes)

•Astacus fluviatulis & Neptunus pelagious

•Daphnia, Cyclops, Balanus

•Scolopendra morsitans, Lycosa ferox

•Phylum: Mollusca (General characters)

•Acanthochiton spinigira, Helix pomatia

•Loligo peadlii, Anodonta sp.

•Phylum: Echinodermata (General characters)

•Astropecten sp.

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Lecture 1

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What do you know about metazoa ?

What do you know about parazoa?

What do you know about eumetazoa? What do you know about ceolom(body cavity )?

What do you know about Mesenchyme cells ?

What do you know about Schizocoelous ?

What do you know about Enterocoelous ?

What do you know about protostomes ?

What do you know about deuterostomes ?

What do you know about Invertebrates ?

AimAim

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Evolution of life on EarthEvolution of life on EarthB

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ProterozoicProterozoic

PhanerozoicPhanerozoic

Cambrian 544-535 myCambrian 544-535 my

Ediacaran 544-600 myEdiacaran 544-600 my

Formation of the EarthFormation of the Earth

First cells (bacteria)First cells (bacteria)

Eucaryotic cellEucaryotic cell

Multicellular lifeMulticellular life

PlantsPlants FungiFungi AnimalsAnimals

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3.0

2.0

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The 32 animal phyla listed in The 32 animal phyla listed in evolutionary relationshipevolutionary relationship

PlacozoaPlacozoaAcathocephalaAcathocephalaEchiuraEchiura

PoriferaPoriferaNematodaNematoda AnnelidaAnnelida

CnidariaCnidaria NematomorphaNematomorpha PhoronidaPhoronida

CtenophoraCtenophoraKinorhynchaKinorhynchaBryozoa (Ectoprocta)Bryozoa (Ectoprocta)

PlatyhelminthesPlatyhelminthesLoriciferaLoriciferaCycliophoraCycliophora

MesozoaMesozoa PriapulidaPriapulida BrachiopodaBrachiopoda

NemerteaNemerteaOnychophoraOnychophora EchinodermataEchinodermata

GnathostomulidaGnathostomulida TardigradiaTardigradiaHemichordataHemichordata

EctoproctaEctoprocta ArthropodaArthropodaChaetognathaChaetognatha

RotiferaRotiferaMolluscaMolluscaChordataChordata

GastroctrichaGastroctrichaSipunculaSipuncula•••*Urochordata*Urochordata

*Cephalochordata•*Cephalochordata•

•*Vertebrata*Vertebrata

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MetazoaMetazoa

The animals have The animals have multicellulr multicellulr

bodybody

Included Included Parazoa Parazoa

and and EumetazoaEumetazoa

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ParazParazoaoa

. .11-- cellular organization:cellular organization: 2- 2- differentiated cells in layersdifferentiated cells in layers

3-3-no true tissuesno true tissues e.g. Porifera (sponges)e.g. Porifera (sponges)

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EumetazoaEumetazoa1 -Diploblastic2 -Triploblastic

2 tissue layers3 tissue layers

)ectoderm and endoderm(ectoderm , endoderm & mesodermmesoderm

No coelom No coelom but there is (central but there is (central canal) forcanal) for digestion, circulation digestion, circulation

important for movementimportant for movement

B

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Body cavities Is that cavity lying between the body wall and the internal

organs.

This cavity may be lacking due to the presence of Mesenchyme cells (e.g.platyhelminthes).

Bilateral animals having distinct body cavity are either coelomate (the most highly organized animals )or pseudocoelomates (e.g. Nematoda).

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Note

Mesenchyme cells: are occupying the space between the body wall and the gut of the animals

1 -the body cavity derived from the blastocoel of the embryo.

2 -this cavity is not lined by mesodermal epithelium.

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Ceolom• Internal fluid-filled cavityInternal fluid-filled cavity

11 - -AceolomAceolom22 - -PseudoceolomPseudoceolom33 - -EuceolomEuceolom

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Pictures for Illustrations

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Pictures for Illustrations

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There are two methods in formation of the ceolom

SchizocoelousSchizocoelousEnterocoelousEnterocoelous

Solid masses of mesoderm split to Solid masses of mesoderm split to form the coelomic cavities As the form the coelomic cavities As the archenteron . archenteron .

mesoderm buds off from the wall of mesoderm buds off from the wall of the archenteron and hollows to the archenteron and hollows to become the coelomic cavities .become the coelomic cavities .

In a protostome .In a protostome .In deuterostomes .In deuterostomes .

Occurs in Annelida, Arthropoda, Occurs in Annelida, Arthropoda, Mollusca, … etcMollusca, … etc

Occurs in Echinodermata, Chordata Occurs in Echinodermata, Chordata … etc… etc..

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The coelomate phyla are divided into two grades based The coelomate phyla are divided into two grades based on differences in their development.on differences in their development.

• 1- These differences center on cleavage pattern, coelom These differences center on cleavage pattern, coelom formation, and blastopore fate.formation, and blastopore fate.

• 2- Many protostomes undergo spiral cleavage, in which planes of cell Many protostomes undergo spiral cleavage, in which planes of cell

division are diagonal to the vertical axis of the embryo.division are diagonal to the vertical axis of the embryo.

• 3-Some protostomes also show determinate cleavage where the fate of Some protostomes also show determinate cleavage where the fate of each embryonic cell is determined early in development.each embryonic cell is determined early in development.

2-deuterostomesdeuterostomes1- protostomesprotostomes

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4-The zygotes of many deuterostomes undergo radial The zygotes of many deuterostomes undergo radial cleavage in which the cleavage planes are parallel or cleavage in which the cleavage planes are parallel or perpendicular to the vertical egg axis.perpendicular to the vertical egg axis.

5-5-Most deuterostomes show indeterminate cleavage Most deuterostomes show indeterminate cleavage whereby each cell in the early embryo retains the whereby each cell in the early embryo retains the capacity to develop into a complete embryo.capacity to develop into a complete embryo.

6- The third difference centers on the fate of the blast pore, The third difference centers on the fate of the blast pore, the opening of the archenteron.the opening of the archenteron.

7-7- In many protostomes, the blastopore develops into In many protostomes, the blastopore develops into the mouth and a second opening at the opposite end the mouth and a second opening at the opposite end of the gastrula develops into the anus.of the gastrula develops into the anus.

8-8- In deuterostomes, the blastopore usually develops In deuterostomes, the blastopore usually develops into the anus and the mouth is derived from the into the anus and the mouth is derived from the secondary openingsecondary opening

The coelomate phyla are divided into two grades based The coelomate phyla are divided into two grades based on differences in their developmenton differences in their development..

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Functions of CeolomFunctions of Ceolom Internal fluid-filled cavity (body cavity)Internal fluid-filled cavity (body cavity)

1.1. Its fluid cushions the internal organs, helping Its fluid cushions the internal organs, helping to prevent internal injury.to prevent internal injury.

2.2. The non compressible fluid of the body cavity The non compressible fluid of the body cavity can function as a hydrostatic skeleton against can function as a hydrostatic skeleton against which muscles can work.which muscles can work.

3. 3. The present of the cavity enables the internal The present of the cavity enables the internal organs to grow and move independently of organs to grow and move independently of the outer body wall.the outer body wall.

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InvertebratesInvertebrates animals that lack vertebrae (classed by a animals that lack vertebrae (classed by a

characteristic they doncharacteristic they don’’t have)t have) 97% of all species on Earth are invertebrate97% of all species on Earth are invertebrate Invertebrates include• Sponges• Cnidarians• Molluscs• Annelids• Nematodes• Arthropods• Echinoderms• (These are all phyla.)

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QuizQuiz 1- Metazoa Included ………and …….? 2- The animals of of Metazoa have have …………… body ? ? 3- Mention three characters of parazoa ? 4- As example of parazoa ……………………..? 5- From your study of zoology what the differentiation of unicellular

and multicellular ? 6- Differ between Metazoa and Parazoa ? 7- What the meaning of true tissue ? 8- Eumetazoa include ……… and ………… ? 9- What the meaning of diploblastic a and triploblastic a ? 10- Compare between diploblastic a and triploblastic a ? 11- Mention three characters of body cavity ? 12- What the function of body cavity ? 13- what the meaning of bilateral animals?

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Mesenchyme cells are ……… The body cavity divided from ……..and……. Ceolom is ………………… Types of ceolom are ……………and…...........and……… Give meaning to : 1- A ceolom 2- Pseudoceolom 3- Euceolom 4- SchizocoelousSchizocoelous 5- EnterocoelousEnterocoelous How the ceolom are formatted (two method) ? The coelomate phyla are divided into two grades based on

differences in their development ………. And……… What the different between them ?

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QuizQuiz

Invertebrates include ……..,………,………..,………….,……and……….

What do you benefit in this lecture ?What do you benefit in this lecture ?

(write in short point and we (write in short point and we

will see it in the next lecture ) will see it in the next lecture )

Prepare the next lecture pleasePrepare the next lecture please

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QuizQuiz