Year 11 P.E
Unit 1:
Term 1
Purpose
The purpose of the skeletal
system is to provide a
basic shape and
structure to our bodies.
It also protects our
internal organs.
The functions of the skeletal system
1.
Body movement
Bones are required for the
muscles to attach. Without
them the muscles would
have nothing to pull on and
contraction would not occur
– no movement!
Functions cont...
2. Support and protection
The skeleton helps to protect the vital and
major organs of the body.
*Imagine every time you hit
your head and there was no
cranium to protect it – you
would be automatically
affecting the brain
Functions cont...
3. Mineral storage site
A number of minerals are stored within the bones which
are important for our health. These minerals are
calcium, phosphorous, sodium and potassium.
Functions cont...
4. Production of blood cells
Inside of the long bones in
our bodies there is a cavity
that is filled with a
substance called Bone
Marrow. In this tissue, new
blood cells are produced,
and damaged blood cells
are repaired.
Arms and Hands
Joints
A joint is the connection between bones. The amount of
movement the joint allows depends on the type of
joint.
Here are 3 types of joints:
- Fibrous joint
- Cartilaginous joint
- Synovial joint
Fibrous Joints
These joints are immovable. They are fixed and are
capable of no movement at all.
There are three types:
- Suture
- Gomphosis
- Syndesmosis
Fibrous - Suture
 Exists between the bones of the skull.
 Are often highly serrated and allow for no movement
at all.
Fibrous- Gomphosis
 This is a peg is socket type of joint
 Example: teeth being held within their sockets
Fibrous - Syndesmosis
 The uniting fibrous tissue is greater in amount than is
the suture joint.
 Usually forms a interosseous membrane or a
ligament.
Cartilaginous Joints
Two bones are united by a continuous area of cartilage.
Two examples:
- Ribs
- Vertebrae
Synovial Joints
The most common and most moveable joints within the
body. These joints are surrounded by a joint capsule,
which contains synovial fluid.
There are many types of synovial joints:
- Ball and socket joint
- Saddle joint
- Condyloid joint
- Hinge joint
- Gliding joint
- Pivot joint
Synovial – Saddle Joint
 The two bone surfaces are shaped as a rider sitting on
a saddle.
 Allows movement back and forth, up and down (but
not rotation).
Synovial - Hinge joint
As the name suggest this joint
acts like a hinge. It is capable
of movement only in one
direction.
Examples?
Synovial – Pivot Joint
 Allows rotation around an axis.
 The bone rotates within a fibro-osseous ring.
Synovial - Ball and socket joint
As the name suggests one bone is the
‘ball’ the other the ‘socket’. This
joint is capable of movement in all
directions.
Synovial – Condyloid Joint
 Modified form of a ball and socket (although less
movement is possible).