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Aims of the Course
Overall aims:
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
oRecognizing the most major coelomic invertebrate phyla
oUnderstanding the biology and internal organs and their function in the different invertebrate
animals
oUnderstanding the taxonomic classification and evolutionary position of the different phyla
Intellectual Skills
oComparing between the taxonomic criteria and organs throughout the different invertebrate
animals
Professional and Practical Skills
oExamining the animals using the microscope and drawing their organs to recognize the
taxonomic criteria
General and transferable Skills
oLearning the participating with student colleagues
oLoving the scientific courses felt their utility in public life
oParticipating in gaining information from the internet
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Syllabus
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
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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 ?
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Evolution of life on Earth
Plants
Fungi
Animals
Phanerozoic
Cambrian 544-535 my
Ediacaran 544-600 my
0.5
Multicellular life
1.0
2.0
Eucaryotic cell
Proterozoic
3.0
First cells (bacteria)
4.0
Formation of the Earth
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The 32 animal phyla listed in
evolutionary relationship
Placozoa
Acathocephala
Echiura
Porifera
Nematoda
Annelida
Cnidaria
Nematomorpha
Phoronida
Ctenophora
Kinorhyncha
Bryozoa (Ectoprocta)
Platyhelminthes
Loricifera
Cycliophora
Mesozoa
Priapulida
Brachiopoda
Nemertea
Onychophora
Echinodermata
Gnathostomulida
Tardigradia
Hemichordata
Ectoprocta
Arthropoda
Chaetognatha
Rotifera
Mollusca
Chordata
Gastroctricha
Sipuncula
••*Urochordata
*Cephalochordata•
•*Vertebrata
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Metazoa
The animals have
multicellulr
body
Included
Parazoa
and
Eumetazoa
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A
Parazoa
1- cellular organization: .
2- differentiated cells in layers
3-no true tissues
e.g. Porifera (sponges)
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B
Eumetazoa
1- Diploblastic
2- Triploblastic
2 tissue layers
3 tissue layers
(ectoderm and endoderm)
ectoderm , endoderm &
mesoderm
No coelom but there is (central
important for movement
canal) for digestion, circulation
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Body cavities
1
2
3
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).
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.
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Ceolom
•
1- Aceolom
Internal fluid-filled cavity
2- Pseudoceolom
3- Euceolom
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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
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.
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The coelomate phyla are divided into two grades based
on differences in their development.
1- protostomes
2-deuterostomes
• 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.
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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
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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.
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Invertebrates
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•
•
•
•
•
•
•
•
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.)
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Annelida
Arthropoda
Mollusca
Echinodermata
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Quiz
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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?
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Quiz
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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- 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 ?
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Quiz
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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
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