2. MAIN CHARACTERISTICS
• They haven’t got a spinal column or an internal skeleton.
• Invertebrates have got different body covering
• Hard shell
• Rigid covering Exoskeleton
• Without protection
4. • They have got a rigid body covering or exoskeleton.
• Their bodies are divided into jointed parts.
• They’ve also got jointed legs that they can bend.
5. THEY CAN BE SEPARATED INTO FOUR GROUPS:
INSECTS
• They have 6 legs.
• Their bodies have 3
parts: head, thorax
and abdomen.
ARACHNIDS
• They have 8 legs.
• Their bodies are
divided into 2 parts:
cephalothorax and
abdomen
CRUSTACEANS
• They have 10 legs
and a very hard
exoskeleton.
• Their bodies are
divided into 2 parts:
cephalothorax and
abdomen.
MYRIAPODS
• They have many
legs.
• Their bodies are
divided into 2 parts:
head and trunk.
abdomen cephalotorax
6. • They’ve got a soft body.
• Most mollusk have a hard Shell. They have also a thin layer next to
their shell called the mantle. It protects their organs.
• Many mollusks have a muscular foot which they use to move
around.
7. THEY CAN BE SEPARATED INTO 3 GROUPS:
BIVALVES
• Have a Shell with 2 parts
called valves.
• Soft body and no head.
• They are filter feeders
(They filter water to
extract nutrients)
GASTROPODS
• Can have a Shell or not.
• They have a head and
body and 4 tentacles.
• Most of them are
herbivores.
CEPHALOPODS
• They have a head with a
mouth and well-developed
eyes.
• They have long arms to
catch their food and some
of them have tentacles.
• Most of them are
carnivores.
8. • Almost all of them live in the ocean.
• Sponges can’t move around. They stay in one place.
• They have a soft body with holes called pores. Sponges are filter feeders.
They filter water through their pores to extract nutrients.
9. • Almost all of them live in
the ocean.
• They are carnivores.
Jellyfish
They float and swim in the ocean.
The mouth is on the underside of the
body.
Polyps
They have a body that is shaped like
a bag.
They have a suction cup at one end
of their body to anchor themselves
to the floor.
10. • They live in the ocean
• They have many tiny feet with
suction cups. They use these
feet to move across the ocean
floor.
