Land vertebrates and humans have an endoskeleton that provides structure, supports weight, and protects organs. It gives shape and supports weight for land vertebrates. Aquatic vertebrates are supported by buoyancy, allowing some to grow very large. Land invertebrates have exoskeletons made of chitin for shape, support, and organ protection. Aquatic invertebrates use exoskeletons or hydrostatic skeletons for support. Plants have various support systems - woody plants use woody tissue and structures like thorns; herbaceous plants use turgor pressure and props or tendrils; aquatic plants rely on buoyancy from air sacs.

2.  The support system of humans
and land vertebrates is an
endoskeleton (internal
skeleton)
 The functions of the
endoskeleton is to :
1. Support the weight of the body
2. Give the body its structure and
shape
3. Produce blood cells
4. Produce soft organs of the
body such as the heart and the
kidneys

3.  Land vertebrates are also
supported by endoskeletons
 The land vertebrates ‘
endoskelton :
1. Give them shape
2. Support their weight
3. Protect their soft tissues and
organs of the body

4.  The body weight of aquatic
vertebrates is supported by the
buoyancy of water
 Their pectoral and pelvic girdles are
very small and weak compared to
those of land vertebrates
 Aquatic vertebrates like the whale
can grow to enormous sizes. This is
because their body is supported by
water so their bones do not have to
support all of their weight

5. Support
System In Land
Invertebrates
Exoskeleton
(external
skeleton)
Hydrostatic
skeleton (fluid-
filled skeleton)

6.  Some invertebrates have hard
external structures for :
1. Maintaining their shape
2. Supporting their bodies
3. Protecting their internal body
organs
4. Aiding movement
 The hard external structures
are called exoskeletons
 The exoskeletons consists of a
hard substance called chitin

7.  Invertebrates with soft bodies
have body fluids to provide
them with shape and support
 The body fluids exert a
pressure on their body walls to
form a hydrostatic skeleton
 The hydrostatic skeleton has
the following functions :
1. Provides support
2. Maintains body shape
3. Aids movement

8. Support System
In Aquatic
Invertebrates
Exoskeleton
Hydrostatic
Skeleton

9.  Aquatic
invwertebrates such
as prawns, crabs,
cockles and snails
are supported by
hard exoskeleton
 The exoskeletons are
very hard because
they contain calcium

10.  Aquatic invertebrates
such as the starfish
and the jellyfish are
supported by a
hydrostatic skeleton
 The fluid pressure in
their bodies gives
them support and
shape

11. Support
System in
Plants
Support
System in
Land Plants
Support
System in
Aquatic Plants

12.  There are 2 types of support system of land
plants, which are :
1. Woody plants
2. Non-woody plants (herbaceous plants)
 Woody plants are supported by woody tissue.
Woody tissue is hard and provides the shape
and strength of the stem to hold itself erect
 Woody plants are also supported by special
structures such as thorns, buttress roots or
clasping roots

13. WOODY TISSUE THORNS
 Woody tissues enables
the plants to grow tall
and erect in order to
obtain sunlight
 Plants such as the rattan,
rose and bougainvillea
have thorns to help them
climb and obtain support
by clinging onto other
plants

14. BUTTRESS ROOTS CLASPING ROOTS
 Plants such as the
casuarina tree have
buttress roots to give
them additional support
 Plants such as the
money plant have
clasping roots to help
them climb on other
plants for support and
to obtain sunlight

15. Support System
In Herbaceous
Plants
Turgor
Pressure
Special
Structures

16.  Herbaceous plants such
as balsam, mustard and
water convolvulus are
supported by turgor
pressure
 The water in the cells
presses against the cell
walls and keeps the stem
hard and erect
 Herbaceous plants will
wilt if there is
insufficient water

17. PROP (ADVENTITIOUS)
ROOTS TENDRILS
 Plants such as corn and
sugar cane have prop
(adventitious) roots to
provide additional
support for plants
 Plants such as bitter gourd
and cucumber plants have
tendrils that twine around
the stems of other plants
in order to climb and
grow upwards

18.  Water provides support to
the aquatic plants such as
water lily, hydrilla, water
hyacinth and duckweed
 Aquatic plants have lots of
air sacs in their stems and
leaves that make them
light and buoyant (able to
float) or suspend in the
water