The skeletal system provides support, protection, movement, and shape to the human body and other animals. There are three main types of skeletal systems - endoskeleton, exoskeleton, and hydrostatic skeleton. An endoskeleton is found in vertebrates and consists of bones or cartilage inside the body. An exoskeleton is an external shell like in insects and crustaceans. A hydrostatic skeleton uses fluid pressure, found in some invertebrates. The skeletal system allows vertebrates and invertebrates to survive on land and in water.

1. Chapter 8
Support and Movement

2.  Support system in humans and animals is
called SKELETON or SKELETAL SYSTEM
ENDOSKELETON
HYDROSTATIC
EXOSKELETON
SKELETON
3 types
of
skeletal
systems

3. HYDROSTATIC
ENDOSKELETON EXOSKELETON
SKELETON
• Inner Frame • Outer Frame • Formed from
• Refers to • Consists of one fluid pressure
bones or layer of hard in space that is
cartilage that is skin derived enveloped by a
inside the body from muscular
of vertebrates substances like system.
calcium
carbonate

4. SUPPORT
MAINTAIN
BODY
BODY SHAPE
WEIGHT
PROTECTS SOFT PROVIDE PLACE
FOR MUSCLE IN
ORGANS INSIDE BODY TO ATTACH
BODY THEMSELVES
ENABLE
LIMBS TO
MOVE

5. SUPPORT BODY MAINTAIN BODY
WEIGHT SHAPE
PROVIDE SURFACE
PROTECT SOFT
FOR MUSCLE TO
TISSUES FROM
ATTACH
DAMAGE
THEMSELVES
ALLOW
MOVEMENT

7. VERTEBRATES INVERTEBRATES
LAND EXOSKELETON
HYDROSTATIC
AQUATIC
SKELETON

8.  Entire weight is supported by its endoskeleton.
 Skeletal system : bigger and stronger than that
of the aquatic animal vertebrate system.
 Bigland animals : Strong and big Pectoral and
Pelvic Girdles to support their body weight
 Four-legged animals : Backbone either curve
upwards or downwards. Enables backbone to
withstand any heavy load acting on the animal

9. Pectoral Girdle
Pelvic
Girdle

10.  Birds: Have hollow bones and air spaces
inside so that the body is lighter.
 Advantages of hollow bones :
 Lighter
 Requires less calcium and phosphorous for
its formation.

11.  Examples : Whales, dolphins
 Smaller and lighter endoskeleton than
land vertebrates.
 Pectoral and pelvic support that is
smaller and lighter.
 Most of body weight is supported by
buoyancy of the water

12.  The buoyancy of the water allows the
size of the aquatic vertebrate animals to
be bigger than land vertebrate animals.

13. ENDOSKELETON
PECTORAL VERTEBRATE
AND PELVIC BONES ARE
GIRDLE FLEXIBLE
SIMILARITIES

15.  Invertebrates are animals that do not have a
backbone.
 Its body is supported by:
 External skeletal system (exoskeleton)
Body fluids (hydrostatic skeletons)

16.  Exoskeleton consists of a layer of hard
skin or shell.
 Examples of invertebrates with hard
outer skin :
 Crabs, spiders, prawns and
scorpions.
 Examples of invertebrates with hard
shell:
 Snails, mussels

17.  For insects, the exoskeleton is called cuticle.
 Cuticle is made of chitin (hard and impermeable to
water)
 Cuticle prevent the insects from growing.

18.  Leeches, worms and octopus do not
have exoskeleton. Their bodies are
soft.
 Use the body fluid (also known as
hydrostatic skeleton system) as
support system.
 The body fluids exert a pressure on
their body walls to form a hydrostatic
skeleton.

20. PLANTS
LANDS AQUATIC
NON WOODY
WOODY
(HERBACEOUS

21.  WOODY PLANTS
 Examples: rubber tree, durian
tree, rambutan tree, and teak tree.
 Supported by woody tissues.
 Woody tissues
– dense, hard on tree trunk.
– made up of xylem tissues.
 Most of the woody plants are tall.

23.  WOODY PLANTS
 Also supported by special structures
 - Buttress roots
 - Clasping roots

24.  Buttress roots
 Examples: durian trees, casuarina trees, and yellow
flame trees.
 Occurs at the base of the trunk where the main roots
branch off at the ground surface and enter the soil.
 Clasping root
 Examples : money plant, certain wild orchid.
 Enable a plant to climb by growing around and
clasping its support.

25.  Non woody plants
 Examples: roses, bougainvillea.
 Supported by turgid cells.

26.  Non woody plants
 Supported by special structures :
 Thorns, Tendrils, Prop Roots
(Adventitious Roots)

27.  Examples: yam, water lily and lotus.
 Supported by water buoyancy.
 Have soft stems that have air space and
their leaves broad with stomata on the
surface.
 Aquatic plants that live in the water have
fine leaves.