INVERTEBRATES
MAJOR PHYLA
Porifera
Cnidarians
Platyhelminthes
Nematoda
Annelida
Mollusca
Echinodermata
Arthropoda
Key Characteristics
Reproduction
*Body made of pores
*Asymmetrical (irregular
shape)
*Sessile
*Filter feeders
*One body opening
*Aquatic
*Stinging cells
*Radial Symmetry (around a
central point)
*One body opening
*Simple nervous system
*Two body forms
(Polyp/Medusa)
*Aquatic
*Flat worms
*Bilateral symmetry (left and
right sides)
*Nerve Cord
*Ganglion (brain-like)
*Open circulatory
*One body opening
*Roundworms
*Bilateral symmetry
*Tapered at both ends
*Open circulatory
*2 body openings
*Segmented Worms
*Bilateral symmetry
*Closed circulatory
*Five “hearts”
*Live everywhere except dry
sand and soil of the desert.
*Gizzards to grind soil
* Muscular foot for movement
*2 body openings
* Bilateral symmetry
*Asexual/Sexual
*Internal/External
*Hermaphrodites
(both male and
female parts)
*Regeneration
Sponges
Examples
*Able to regenerate
Unique Facts
*Asexual-Polyp
*Sexual-Medusa
*Budding
Jelly fish
Hydra
Corals
Sea anemones
*The Australian Box Jelly
is invisible to swimmers
and can kill within
minutes of a sting.
*Asexual/Sexual
*Hermaphrodites
*Regeneration
Tapeworms
Flukes
Planarians
Tapeworms used to be
given as a form of weight
control. They can reach
up to 10 m in length.
*Asexual/Sexual
Hookworm
Pinworm
Trichinella
Ascaris
1/3 of the population
suffers from problems
caused by roundworms.
*Asexual/Sexual
Earthworm
Leeches
Bristleworms
Each segment can have a
special function.
Leaches can be used in
medicine.
*Sexual
*Mollusks are the first
animals to have
respiratory structures.
*Spiny endoskeleton
*Suction tipped appendages
*Radial Symmetry
*Water vascular system
*Simple nervous system
*Live only in salt water
*Asexual/Sexual
*Regeneration
*Jointed Appendages
*Exoskeleton
*Bilateral symmetry
*Molting (sheds exoskeleton)
*Efficient respiratory
structures called spiracles
*acute/keen senses
*central nervous system
*Sexual
Bivalves 2 shells
Clam/Scallop
Gastropods 1 shell
Snails/Slugs
Cephalopods no shell
Octopus/Squid
Star fish
Brittle stars
Sea Urchins
Sand Dollars
Sea cucumbers
Sea lilies
Feather stars
Insects-ants
(diplopoda-millipedes)
(chilopoda-centipedes)
ArachnidsSpiders/Scorpions
CrustaceansLobster/Crab
Cray Fish/Barnacle
*Live sand dollars are
purple not white.
*Insects is the largest
group of Arthropods
*The bite of a centipedes
is poisonous.
Name:________________________ Date: _______ Block: ____
Invertebrates
a. Porifera
b. Platyhelmenthes
c. Echinodermata
d. Cnidarians
e. Nematoda
f. Molluska
g. Annelida
h. Arthropoda
____ Spiny exoskeleton
____Includes sea stars
____Molts (shedding of exoskeleton)
____Jointed appendages
____Stinging cells
____Includes earthworms and leeches
____Includes insects
____Includes worms that are tapered at both ends
____Muscular foot
____Includes tapeworms and planarians
____Flatworms
____Includes octopus and squid
____Round worms
____Includes bivalves (clams/oysters)
____Segmented worms
____Includes hydra and jellyfish
____ Includes sponges
_____Suction-tipped appendages
Invertebrate Phyla
Porifera
Cnidarians
(Coelenterates)
Platyhelmenthes
Nematoda
Annelida
Mollusca
Echinodermata
Arthropoda
Distinguishing Characteristics
Example Organisms