SKELETON
SUPPORT
Louisa Degabriele, Ilona Borg,
Drew Christina Demicoli, Eve Zammit
WHY DO WE NEED A SKELETON?
 Skeletons
support
our body and give
it its shape.
 Without a skeleton,
animals would not
be able to move.
DO ALL CREATURES NEED A
SKELETON?
 Not
all creatures
need to support
their body.
 Jellyfish spend their
lives in water and
this makes them not
need to have a
skeleton at all.
DO ALL LAND-LIVING
CREATURES NEED A SKELETON?
 Land
living
creatures must
have a skeleton
in
order
to
support
their
body and help
them to move.
 Different
animals
use
different types of
skeletons:
WHAT DIFFERENT
SKELETONS EXIST?
TYPES
 Earthworms
OF
support
their body by means
of a liquid which is
found right in the
centre of the body.
The liquid keeps the
body firm ... just like
a
full
tube
of
toothpaste!
 The muscles of the
worm’s body press
against the liquid and
this helps the worm
to move.
Problem: Any weak points for this
type of skeleton?

Unfortunately
this
skeleton offers no
protection and these
types of animals can
be damaged very
easily... think of a
punctured toothpaste
tube!
WHAT OTHER DIFFERENT TYPES
OF SKELETONS EXIST?
 Snails,
oysters,
clams and squid,
protect their soft
body with a hard
shell made of rock
like material.
 When some of these
animals
are
threatened they can
hide
behind
or
inside the shell as if
hiding behind a
SHIELD.
WHAT OTHER DIFFERENT TYPES
OF SKELETONS EXIST?
 Insects,
crabs and
spiders
have
a
special
OUTER
skeleton
which
covers all parts of
the body ... just like
a knight’s armour!
 Of course it has to
have JOINTS in
order
for
these
animals to move.
Problem: Any weak points for this
type of skeleton?

The skeleton does not
grow with the animals,
and so every so often, the
animals will have to
SHED its old skeleton,
while a new soft skeleton
will
be
growing
underneath, which will
allow the animal to grow
until the new skeleton
hardens. It’s like taking
off a piece of clothing that
no longer fits!
WHAT OTHER DIFFERENT TYPES
OF SKELETONS EXIST?
 Starfish
and sea
urchins
have
plates of skeleton
under the skin.
 They
also have
SPINES
coming
out of the body
which can help the
animal to move ...
and can also scare
off other animals!
WHAT OTHER DIFFERENT TYPES
OF SKELETONS EXIST?
Backboned animals – or
VERTEBRATES – have a
skeleton which is found
INSIDE the body. These
animals usually feel soft on
the outside but have a frame
of hard BONE on the inside.
 Bones are made of stronger
material.
 They are also living and so
grow with the body of the
animal – so they do not need
to be shed every so often.

Problem: Any weak points for this
type of skeleton?
 The
skeleton does
not protect the
outer parts of the
body, like the skin
and muscles, so
these can easily
be damaged.
SO .....
The best working skeleton is in
fact that found in vertebrates! It
can best support the body with a
strong tough frame and can offer a
good protection to the delicate
organs inside the body.
It is also a LIVING skeleton, so
does not need to be shed and be
replaced.