Porifera
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Asymmetrical
They don't have mouth or anus because they have pores to facilitate the circulation of material
Could have silica or calcium carbonate based spicules for structural support for example sea
sponges
Cnidaria
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Obtain a radial symmetry
They just have a mouth, have a ​single entrance body cavity
Possibly have tentacles with stinging cells for capturing and disabling their prey
For example jellyfish, sea anemones and coral
Platyhelminthes
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Their symmetry is bilateral
Have a mouth, have a single entrance body cavity
Their body shape is flattened to increase SA:Vol ratio
Could be parasitic
Example: tapeworms and planaria
Annelida
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Their symmetry is bilateral
Have a separate mouth and anus
Body consists of ringed segments with specialisation of segments
Examples include earthworms and leeches
Mollusca
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Their symmetry is bilateral
Have a separate mouth and anus
Body consists of a visceral mass, a muscular foot and a mantle
Could produce shells
Examples: snails, slugs, octopi, squid and bivalves
Arthropoda
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Their symmetry is bilateral
Have a separate mouth and anus
Their body sections are jointed body sections and have a hard exoskeleton (
Examples include insects, crustaceans, spiders, scorpions and centipedes