The Skeleton
Bones – An introduction
• The human skeleton consists of 206 bones. We are
actually born with more bones (about 300), but many
fuse together as a child grows up. These bones support
your body and allow you to move.
• The longest bone in our bodies is the femur (thigh
bone). The smallest bone is the stirrup bone inside the
ear. Each hand has 26 bones in it. Your nose and ears
are not made of bone; they are made of cartilage, a
flexible substance that is not as hard as bone.
The Axial & Appendicular Skeleton
The skeleton is split into these 2 categories:
Axial Skeleton – Skull, vertebral
column and ribcage
Appendicular Skeleton –
Limbs, wings and pelvis
COMPLETE WORKSHEET 1 C
The Vertebral Column
Is there movement?
Yes
Very limited
movement to
create a stable
structure for the
organs found
inside the ribcage
2 lumbar vertebrae
are moveable, 3 are
fused, therefore no
movement
Fused, therefore
no movement
ANSWER THESE QUESTIONS
1. How many bones are there in the human body?
2. What is the longest bone in the body?
3. Where in the body is the smallest bone?
206
femur
the ear
4. Your nose and ears aren’t made of bone but what other
substance?
cartilage
5. The skeleton is defined into two categories, what are they?
axial & appendicular
6. How many sections make up the vertebral column?
5
Joints
What is a joint?
A place where two or more bones meet
http://www.youtube.com/watch?v=zWo93GJpr8&feature=PlayList&p=1D1576CEF4196B76&index=5
What are the types of joint?
There are 3 types of joint:
• Freely Moveable / Synovial
• Slightly Moveable / Cartilaginous
• Immoveable / Fixed
There are 6 types of freely moveable or
synovial joints joints in which we need to know
3 of them:
http://www.youtube.com/watch?v=BXoMa2bVC18&feature
=related
1. BALL AND SOCKET JOINTS
2. HINGE JOINTS
3. PIVOT JOINT
4. CONDYLOID- AS IN WRIST
5. GLIDING- AS IN ANKLE AND HAND
6. SADDLE- AS IN THUMB
Types of Joint
Movement
Example of Joint
Fixed joints (Fibrous)
No movement
Cranium
Sacrum
Slightly moveable joints
(cartilaginous)
Limited movement
Vertebral column
(thoracic vertebrae)
Carpals / Tarsals
Synovial joint / freely movable
Free movement
Ball and socket
Hinge
Sliding
Saddle
Pivot
Activity
Write down 5 sports actions and beside each
write down the main parts of the body that
Move, the bones and the type of joint and joint
action and movement possible for that action
E.g. Snooker. Cueing the white ball. Right arm
humerus, ulna, radius, carpal, metacarpal,
phalanges. Elbow, synovial, hinge lots of
movement
Function of the Skeleton – worksheet 1e
Your skeleton has many different functions to enable you
to live and survive. These include:
• Protection
• Movement
• Shape
• Muscle/organ attachment
• Blood cell production
• bone growth
•http://www.youtube.com/watch?v=zZxLfJRd4cs
• Protection – Many of the internal organs in your body
are protected by bone. The flat type bones of your body
function in this way (sternum, pelvis, cranium etc.)
• Movement – Your body is able to move because of the
co-operation between its muscles and bones. The
muscles are attached to the bones of the skeleton,
creating a lever and joints system that allows the body to
move.
• Shape – Your skeleton provides the framework to give
your body its shape. Without it, you would look like a
blob of jelly.
•Muscle/organ – Your body provides a support system to
attach muscles, organs, arteries, veins etc.
• Blood cell production – Bone also produces blood cells.
This occurs in the marrow of the bone that is found in the
epiphysis (end) and diaphysis (shaft) of all long bones.
• Bone growth – As we discovered earlier bone has the
ability to be broken down and reformed. This is called
ossification.
http://www.bbc.co.uk/science/human
body/body/index_interactivebody.sht
ml
Bone Growth
Bones start off as cartilage as a
fetus. As the fetus develops,
mineral are laid down and the
cartilage becomes harder and
less flexible.
This process is called
‘ossification’ and can continue
until you are 30 (although it
usually stops between 18-21)
Bone is continually being broken down and replaced; this process is done by 2
different cells:
Osteoclasts break down old bone and clean the bone environment.
Osteoblasts are bone forming cells that help to develop new bone throughout life.
These will replace about 10% of bone every year; this means that no matter how
old we are our skeleton is no older than 10 years old.
Structure of a Long Bone
Epiphysis – Ends of the bone.
Diaphysis – Long shaft of the bone.
Articular cartilage – thin layer of blueish
cartilage covering each end of the bone.
Periosteum – thin outer layer of the bone. It
contains nerves and blood vessels that feed the
bone.
Compact bone – This is hard and resistant to
bending.
Spongy bone – this lies in layers within the
compact bone. It has a honeycomb
appearance and gives bones their elastic
strength.
Medullary cavity – the hollow space down the
middle of the compact bone and contains bone
marrow. Bone marrow produces blood cells
and store fat.
Types of Bone – worksheet 1f
Types of Bone
Example found in body
Example of function
Short bones
Carpals
Metatarsals
Small movement
Long bones
Femur
Humerus
Large movement
Cell production
Irregular bones
Vertebrae
Protection
Support
Flat or plate bones
Pelvic girdle
Cranium
Attachment of muscle
Protection
Sesamoid bones
Patella
Under 1st metatarsal in
the foot
Prevention of hyper-extension of the
femur.
Protection of the tendon and increase
movement of the joint.
HOW DO WE CLASSIFY BONES ?
Bones are classified according to their function.
1.(Protection) FLAT BONES
2.(Protection) IRREGULAR BONES
3.(Levers) LONG BONES
4.(Small movements)SHORT BONES
Movement – worksheet 1g
Movement Term
Description of movement
Abduction
The limb moves away from the midline of the body
Adduction
The limb moves closer to the mid-line
of the body
Rotation
The limb rotates at the joint to cause
movement at the distal end.
Extension
The joint angle of two or more bones
increases, or the limb straightens
Flexion
The joint angle of two or more bones
decreases, which results in a bending
position
Movement Term
Description of movement
Circumduction
Circumduction is a movement in which
flexion, abduction, extension and
adduction movements are combined in
sequence
Rotation
Medial rotation is to turn inward.
Lateral rotation is to turn outward.
Pronation
Pronation is to rotate the forearm so
that the palm faces backward.
Supination
Supination is to rotate the forearm so
that the palm faces forward.
Circumduction
Movement Term
Description of movement
Plantar flexion
the movement which increases the angle
between the foot and the leg
Dorsiflexion
the movement which decreases the angle
between the foot and the leg
Inversion
The act of turning from outside to inside
Eversion
The act of turning inside out
Hyper Extension
Hyperextension is a straightening
movement that goes beyond the normal,
healthy boundaries of the joint.
Effects of Exercise
The skeletal system changes due to exercise. However, the changes depend on
the type of exercise that individuals may participate in. The changes can be
short or long term:
Short term: When you participate in exercise your body moves more rapidly
which means that joints need to work more. This extra demand on the joints
causes a release of synovial fluid around the joint site that helps movement
occur more easily.
Long term: Hyaline cartilage increases in its thickness around the joint site as
exercise continues. This can help with preventing the surface of the bones from
wearing away too soon.
Regular participation in weight bearing exercises also
helps to increase bone density, resulting in the bones
becoming stronger.
Describing the body’s parts and position
Anterior – Front of body
Midline
Posterior – Back of body
Superior – closer to head
Superior
Inferior – further away from head
Medial – closer to midline of
body
Inferior
Lateral – further away from
midline of the body
Lateral
Proximal
Proximal – nearer point of
attachment of main structure of
body
Medial
Distal
Distal – further away from point of
attachment to the main structure of
the body
Anterior
Posterior