1. Digestive system, respiratory
All animals have 3 germ layers = TRIPLOBLASTIC Except: sponges, jellyfish, anemones = DIPLOBLASTIC
Endoderm
Mesoderm
Ectoderm
Digestive system, respiratory
Muscle, excretory, bones,
circulatory
Outer skin, brain, nervous system

2. Types of Coeloms (See-Lums)
No cavity (space) around organs
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ACOELOM = “without space”

3. FLATWORMS are ACOELOMATES!

4. Types of Coeloms (See-Lums)
Space around organs but only lined with mesoderm on one side (lines body wall BUT NOT around gut)
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PSEUDOCOELOM

5. ROUND WORMS are PSEUDOCOELOMATES!

6. Kinds of Coeloms (See-Lums)
EUCOELOM: Body cavity (space) lined on BOTH sides by mesoderm
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EUCOELOM = TRUE COELOM = COELOM

7. EUCOELOMATES
ALL VERTEBRATES & MOST
INVERTEBRATES

8. 3 Types of Coeloms ACOELOM EUCOELOM PSEUDOCOELOM ectoderm mesoderm
endoderm
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9. FUNCTIONS of having a COELOM (body space):
Provides space/cushion internal organs
In animals without a skeleton- Fluid in coelom space can act as a HYDROSTATIC skeleton
In animals without blood vessels- Fluid in coelom space can circulate nutrients and oxygen to cells

10. ADVANTAGE OF a EUCOELOM?
Digestive organ muscles and body wall muscles come from MESODERM in different places so organism can digest food and move at same time.
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