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VCE Physical Education
Unit 1
SKELETAL SYSTEM
Human Skeleton
FUNCTIONS

SUPPORT

PROTECTION

MOVEMENT

PRODUCTION & STORAGE
organs and tissues of the body are held
in place by the skeleton.
-
– provides a rigid surface for
protection of vital organs ie. cranium protects the brain
– bones provide a base for muscle
attachment. It allows movement of the body through
using the bones as levers.
– bones provide a
site for manufacture of red & white blood cells and
storage of minerals. Ie.calcium
STRUCTURE OF SKELETON


(1)
(2)
There are about 206 bones found in an adult skeleton.
The bones are divided into two main groups
AXIAL SKELETON
APPENDICULAR SKELETON
AXIAL SKELETON
• The axial skeleton forms the
basic structure supporting
the rest of the skeleton.
• It consists of:
– Skull
– Vertebral column
– Rib cage
AXIAL SKELETON
SKULL
Cranium consists of 8
bones fused together.
Face has 14 bones. Most
are fused, whilst others
like the mandible (lower
jaw bone) can move
independently
Fusion of the human skull
AXIAL SKELETON
VERTEBRAL COLUMN
Divided into 5 main regions
(1) Cervical spine (7)
(2) Thoracic spine (12)
(3) Lumbar spine (5)
(4) Sacrum (5)
(5) Coccyx (4)
The 5 sacrum vertebrae and 4
coccyx vertebrae are fused to
form one solid bone.
Cervical, Thoracic, Lumbar, Sacrum
and Coccyx
AXIAL SKELETON
• ATLAS – first cervical vertebra
• AXIS – second cervical vertebra
• Spinal chord runs down the canal
formed by the vertebra being
stacked on top of one another.
• Intervertebral Discs are found
between each vertebrae and keep
spine flexible and they absorb
shock
• Coccyx remnance of a tail
AXIAL SKELETON
THORAX
• 12 pairs of ribs
• Joined to thoracic vertebrae
• Top 10 ribs joined to
sternum
• Remaining two have “free”
ends – ‘floating’
APPENDICULAR SKELETON
• Forms mainly the
extremities of the body
and their connections to
the axial skeleton
• Consists of
- limbs (arms & legs)
- shoulder and pelvic
girdles
APPENDICULAR SKELETON
THE ARM AND HAND
APPENDICULAR SKELETON
THE LEG AND FOOT
TYPES OF BONE TISSUE
(1) COMPACT BONE
TISSUE



Heavy, dense, strong
bone tissue
Ivory appearance &
covers the complete
bone
Thickest at the centre
of the shaft
TYPES OF BONE TISSUE
(2) CANCELLOUS BONE
TISSUE
or “spongy bone”
 Honeycomb
appearance
 Strong, hard & less
dense than compact
bone
 Found mainly ends of
bones
TYPES OF BONES
Bones are classified into 5 groups according to their shape:
 LONG BONES – incl. humerus, radius, tibia and
phalanges
 SHORT BONES – incl. carpals and tarsals
 FLAT BONES – incl. skull, pelvis, ribs and shoulder
blades (Flat bones protect vital organs and provide sites
for muscle attachment)
 IRREGULAR BONES – incl. facial and vertebrae
 SESAMOID BONES – incl. patella (bones which are
found encased by muscle)
TYPES OF BONES
Short bones (carpals)
ANATOMICAL TERMINOLOGY
TERM
Superior
Inferior
Anterior (ventral)
DEFINITION
Toward the Head
Toward the feet
Front
Posterior (dorsal)
Medial
Lateral
Back
Toward the midline (inside)
Toward the side (outside)
Proximal
Distal
Prone
Nearer the trunk
Further from the trunk
Face down (on stomach)
Supine
Face up (on back)
BODY GROWTH

Changing rate of growth to the body is affected by two
things – height and weight.

Differs from time to time during life and differs for various
body parts.
Adolescent Growth Spurt

Most rapid gains in height within first 1 to 2 years of life

By 2 years of age – an individual has reached half their
adult height.

Pubertal growth spurt is the next major increase in
height. (11-12 years for girls and 13-14 years for boys
approximately)

Body changes length in the following pattern
(1) Feet and hands develop first (increase in size)
(2) Lower legs and forearms grow rapidly
(3) Thighs and upper arms increase in length
(4) Finally trunk develops in length
The width of the body develops next, as the shoulders and
pelvis widens
SHORT BONE GROWTH

The outside of a short bone is formed by cartilage. The
cartilage grows until the final shape of the bone is
formed.
 Meanwhile the bone ossifies (hardens into bone) from
the inside outwards. Eventually all cartilage is ossified,
and growth is complete.
LONG BONE GROWTH
Two growth processes responsible for done development.
First process:
 OSTEOBLASTS (bone builders) – add bone to the
outside surface, enlarging and elongating the bone.
 OSTEOCLASTS (bone eaters) – tunnel out the marrow
cavity and internal spaces (these work at the same time
as osteoblasts.)
Second process (greatest growth occurs):
 EPIPHYSEAL PLATES (growth plates) found at either
end of the bone where the shaft (diaphysis) meets the
head or base (epiphysis). These growth plates are
made of cartilage cells which multiply rapidly and the
outside cells ossify, increasing the length of the shaft.
LONG BONE GROWTH
GROWTH HORMONE (GH)

GH - Responsible for most growth changes occurring.

Produced by the pituitary gland, at the base of the
brain.

Growth Hormone:
(1) stimulates the epiphyseal plates to expand and form
bone
(2) increase protein uptake by the muscles, therefore
increasing muscle growth
FACTORS AFFECTING GROWTH





Basic control of growth is
genetic
Starvation and Malnutrition can
delay growth spurt
Major illness slow down growth
Regular exercise has many
growth benefits
Aerobic exercise also
increases the size and
efficiency of the heart, blood
and lungs. However, repetitive
long distance training for
marathons or triathlons may
damage epiphyseal plates.
SKELETAL SYSTEM
Reference: VCE Phys Ed Book 1 (your text)
Chapter 1 pg 3-10
The End