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How do we classify invertebrate animals?
Living things
Molluscs
These invertebrates have soft
bodies, and most also have
a hard shell. They absorb
oxygen through gills, and
reproduce by laying eggs.
Mussels, snails and oysters
are examples of molluscs.
Echinoderms
These
animals
have bodies
covered with
sharp
spikes
.
Some also
have arms and
tentacles
.
Some echinoderms
have gills: others absorb
oxygen through their skin.
Echinoderms are oviparous.
Starfish are an example of
echinoderms.
Coelenterates
These animals
have a soft body.
Some have
long tentacles.
They absorb
oxygen through
their skin. They
reproduce by growing a
bud
,
or small body part. Eventually
the bud breaks off and
grows into a new organism.
Jellyfish are an example of
coelenterates
.
Arthropods
These invertebrates have an
exoskeleton
and jointed legs
that bend. Some arthropods
have simple lungs. Others,
like crabs
and
lobsters,
absorb
oxygen
through their gills.
Arthropods are oviparous.
Insects, spiders and
crustaceans are arthropods.
Porifera
These
invertebrates
have a soft
body with
holes called
pores
. They
absorb
oxygen and
nutrients
through the pores. Like
coelenterates, they reproduce
by forming buds. Sponges
belong to this group.
Annelids
These animals
have a long,
soft body that
is divided into
rings called
segments
. Some annelids
absorb oxygen through their
skin, but others have gills.
Annelids can reproduce by
budding, like porifera and
echinoderms, but some
are oviparous. Worms and
leeches are annelids.
1
Vertebrate or invertebrate? Make a table. Add more examples.
mouse crab worm duck
G
E T T I N G S T A R T E D
Animals that don’t have a spinal cord are called invertebrates.
Invertebrate animals are classified into six groups: arthropods,
molluscs, porifera, coelenterates, echinoderms and annelids.
