1. Coelomic InvertebratesBy
Prof. Dr. Ola Abu Samak

2. Aims of the Course Overall aims: Intended learning Outcomes (ILO’s)
Recognizing the diversity of God’s creation of different coelomic invertebrates animals
Developing the familiarity with the coelomic invertebrate phyla
Acquisition of facts and concepts on the biology, body organs and their function of invertebrate animal
Recognizing of the importance of this course and other scientific courses taught in this program
Increasing the teamwork skills and using of internet and microscopes
Intended learning Outcomes (ILO’s)
Knowledge and Understanding
Recognizing the most major coelomic invertebrate phyla
Understanding the biology and internal organs and their function in the different invertebrate animals
Understanding the taxonomic classification and evolutionary position of the different phyla
Intellectual Skills
Comparing between the taxonomic criteria and organs throughout the different invertebrate animals
Professional and Practical Skills
Examining the animals using the microscope and drawing their organs to recognize the taxonomic criteria
General and transferable Skills
Learning the participating with student colleagues
Loving the scientific courses felt their utility in public life
Participating in gaining information from the internet

3. Syllabus Phylum: Mollusca (General characters)
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.

4. Lecture 1
Introduction

5. Aim 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 ?

6. Evolution of life on Earth
Plants
Fungi
Animals
Phanerozoic
Cambrian my
Ediacaran my
0.5
Multicellular life
1.0
Billions of years before present600 my
2.0
Eucaryotic cell
Proterozoic
3.0
First cells (bacteria)
4.0
Formation of the Earth

8. The 32 animal phyla listed in evolutionary relationship
Echiura
Acathocephala
Placozoa
Annelida
Nematoda
Porifera
Phoronida
Nematomorpha
Cnidaria
Bryozoa (Ectoprocta)
Kinorhyncha
Ctenophora
Cycliophora
Loricifera
Platyhelminthes
Brachiopoda
Priapulida
Mesozoa
Echinodermata
Onychophora
Nemertea
Hemichordata
Tardigradia
Gnathostomulida
Chaetognatha
Arthropoda
Ectoprocta
Chordata
Mollusca
Rotifera
•*Urochordata
*Cephalochordata•
*Vertebrata
Sipuncula
Gastroctricha

9. Included Parazoa and Eumetazoa The animals have multicellulr body

10. A
Parazoa
. 1- cellular organization: 2- differentiated cells in layers 3-no true tissues e.g. Porifera (sponges)

11. Eumetazoa 2- Triploblastic 1- Diploblastic B
3 tissue layers
2 tissue layers
ectoderm , endoderm & mesoderm
(ectoderm and endoderm)
important for movement
No coelom but there is (central canal) for digestion, circulation

13. 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). 1 2 3
Mesenchyme cells :
are occupying the space between the body wall and the gut of the animals
Note
1- the body cavity derived from the blastocoel of the embryo .
2- this cavity is not lined by mesodermal epithelium.

14. Internal fluid-filled cavity
Ceolom
Internal fluid-filled cavity
1- Aceolom
2- Pseudoceolom
3- Euceolom

15. Pictures for Illustrations

16. Pictures for Illustrations

17. There are two methods in formation of the ceolom
Schizocoelous
Enterocoelous
Solid masses of mesoderm split to form the coelomic cavities As the archenteron .
mesoderm buds off from the wall of the archenteron and hollows to become the coelomic cavities .
In a protostome .
In deuterostomes .
Occurs in Annelida, Arthropoda, Mollusca, … etc
Occurs in Echinodermata, Chordata … etc.

19. The coelomate phyla are divided into two grades based on differences in their development.
1- These differences center on cleavage pattern, coelom formation, and blastopore fate.
2- Many protostomes undergo spiral cleavage, in which planes of cell division are diagonal to the vertical axis of the embryo.
3-Some protostomes also show determinate cleavage where the fate of each embryonic cell is determined early in development.
1- protostomes
2-deuterostomes

20. The coelomate phyla are divided into two grades based on differences in their development.
4-The zygotes of many deuterostomes undergo radial cleavage in which the cleavage planes are parallel or perpendicular to the vertical egg axis.
5-Most deuterostomes show indeterminate cleavage whereby each cell in the early embryo retains the capacity to develop into a complete embryo.
6- The third difference centers on the fate of the blast pore, the opening of the archenteron.
7- In many protostomes, the blastopore develops into the mouth and a second opening at the opposite end of the gastrula develops into the anus.
8- In deuterostomes, the blastopore usually develops into the anus and the mouth is derived from the secondary opening

21. Functions of Ceolom Internal fluid-filled cavity (body cavity)
1. Its fluid cushions the internal organs, helping to prevent internal injury.
2. The non compressible fluid of the body cavity can function as a hydrostatic skeleton against which muscles can work.
3. The present of the cavity enables the internal organs to grow and move independently of the outer body wall.

22. Invertebrates
animals that lack vertebrae (classed by a characteristic they don’t have)
97% of all species on Earth are invertebrate
Invertebrates include
Sponges
Cnidarians
Molluscs
Annelids
Nematodes
Arthropods
Echinoderms
(These are all phyla.)

23. Annelida
Arthropoda
Mollusca
Echinodermata

24. Quiz 1- Metazoa Included ………and …….?
2- The animals of Metazoa 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?

25. Quiz 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- Schizocoelous
5- Enterocoelous
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 ?

26. Quiz What do you benefit in this lecture ?
Invertebrates include ……..,………,………..,………….,……and……….
What do you benefit in this lecture ?
(write in short point and we
will see it in the next lecture )
Prepare the next lecture please