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PE - Anatomy and Physiology
Please make notes and then complete tasks 1-4.
Introduction
The skeletal and muscular systems are very closely linked and are often referred to as the musculo-
skeletal system. All sporting techniques, from the powerful executions needed in a game of rugby to
the smooth elegance displayed by a gymnast on the beam, require the skeletal and muscular
systems of our bodies to work together effectively and efficiently
Our skeleton provides the framework that allows movement to take place and our skeletal muscles
provide the energy to pull our bones and joints into the correct positions needed for different types
of physical activity. In this chapter we will look at the structure and function of both of these body
systems, which will help us understand how we move our bodies during physical activity. We will
learn to describe anatomically the movements that occur at the joints and to explain how these
movements take place in terms of the muscles in action and the type of contraction occurring. We
can then use this knowledge to carry out a full movement analysis for specific sporting techniques.
Towards the end of the chapter we will look at the role that muscle fibres play in their contribution
to movement by studying the different types of muscle fibre and seeing how each is adapted to suit
certain forms of physical activity. This activity could be very powerful such as that demonstrated by
Kevin Pieterson hitting a six, or more endurance based such as that required by David Walliams
when he swam the English Channel .Like all human structures, bones, joints and muscles can suffer
from disorders from time to time . These can be due to an injury caused whilst taking part in exercise
or a condition that has developed due to a lack of exercise. So, we will try to critically evaluate the
impact that an active lifestyle has in maintaining a healthy musculo-skeletal system.
EXAM TIP
Movement analysis is a very popular topic
about which examiners like to test your
knowledge. Make sure you are confident at
applying the knowledge you have gained in
this chapter to different types of sporting
movements. Remember that practise makes
perfect!
KEY TERMS
SKELETON
The bony framework upon which the rest of
the body is built. It provides attachments for
the muscular system and carries and protects
the cardiovascular and respiratory systems.
SKELETAL MUSCLES
This attaches to and moves the skeleton. It is
often termed striated muscle because it has
obvious stripes on it caused by the long muscle
fibres of which it is composed. It is also called
voluntary muscle because it is the only type of
muscle under our conscious control.
JOINT
A place on the body where two or more bones
meet.
The skeletal system: Introduction to the skeleton
The skeleton is the structure that gives us our shape, provides protection for our internal organs and
offers a supportive framework for the attachment of muscles therefore facilitating movement. Our
bones also act as a site for the production of blood cells and a store of minerals, particularly calcium.
The average human adult has 206 bones that are divided into two different parts, the axial and the
appendicular skeleton:
206 bones
AXIAL SKELETON APPENDICULAR SKELETON
Skull Shoulder girdle and upper limbs
Thoracic girdle Pelvic girdle and lower limbs
Vertebral column
You do not need to know the names of all the bones in the body but you do need to be familiar with
the main bones that make up the major joints that we use for movement. Use the diagram on the
next page to familiarise yourself with their names.
APPLY IT - The skeleton has five main functions: SUPPORT, PROTECTION, MOVEMENT,
BLOOD CELL PRODUCTION and MINERAL STORE. Give examples of how the functions of
the skeleton enable you to carry out your every-day needs and routine.
EXAM TIP
On your exam paper you will not be required
to label a skeleton but it is recommended that
you can identify the bones that articulate to
form the following joints: wrist, radio-ulnar,
elbow, shoulder, spine, hip, knee and ankle.
REMEMBER – The clavicle, scapula and pelvis belong to the appendicular
skeleton. It is a common error to link them to the axial skeleton.
KEY TERMS
APPENDICULAR SKELETON
The bones of the upper and lower limbs and their girdles that join to the axial skeleton
AXIAL SKELETON
This forms the long axis of the body and includes the bones of the skull, spine and rib cage.
LIGAMENT
A tough band of fibrous, slightly elastic connective tissue that attaches one bone to another.
It binds the ends of bones together to prevent dislocation
TENDON
A very strong connective tissue that attaches skeletal muscle to bone.
TASK 1
1. List the individual bones that make up the following regions of the skeleton:
Thoracic girdle
Shoulder girdle
Upper limb
Pelvic girdle
Lower limb
2. Classification of joints: Identify the joints numbered 1-8 in the diagram below and list
the bones that articulate to form each of the joints you have identified. Record your
results in the table:
Joint number
Joint name Bones that articulate Helpful hints
1
List three bones
2
This is an easy one!
3
List three bones
4
List only two bones – find out the names of the bony features that
articulate
5
Name the bones that make up the spine –
find out the five areas of the spine and the
names of the 2 bones at the top of the spine
6
List only two bones – find out the names of the bony features that
articulate
7
Be careful here! List only two bones
8
Tricky! List three bones, but not the
tarsals
TYPES OF BONE AND CARTILAGE
EXAM TIP
Your examiner is not going to directly test you on the detail of types of bone and cartilage. However,
you will need to have a basic understanding of the structure and growth of a long bone to appreciate
the condition of osteoporosis and to understand the occurrence of growth plate disorders. You will
also need to understand the role that articular cartilage plays in the degenerative disease of
osteoarthritis.
Bone is made of collagen fibres filled with minerals, mainly calcium salts. There are five types of
bone in the skeleton that are classified according to their shape. One of these types is the long
bone, which is longer than it is wide and consists of a shaft, called the diaphysis and two ends,
each called the epiphysis. The epiphysis is covered by articular cartilage that acts as a cushion to
absorb shock and also prevents friction during joint movement. It is one of the three types of
cartilage that we have in our bodies.
Children and young adults have a region between the diaphysis and each epiphysis called the
growth plate, which is responsible for promoting longitudinal bone growth until physical maturity.
Bones also contain cavities that are filled with bone marrow, which generates new blood cells.
Long bones have a large cavity in the diaphysis and a network of small cavities in each epiphysis.
TASK 2
1. A long bone is one of the five types of bone found in the skeleton. Identify and give
examples of the other four types of bones.
2. Articular cartilage is one of the three types of cartilage found in the human body. Identify,
outline the function and give examples of the other two types of cartilage.
REMEMBER
All bones of the limbs, except the patella and the bones of the wrist and ankle are long bones.
Even the bones of your hands and feet (metacarpals, metatarsals and phalanges) are long bones.
KEY TERMS
COLLAGEN
A fibrous protein with great strength that is the main
component of bone.
CALCIUM
The mineral stored in bone that keeps it hard and strong.
99% of the body’s calcium is stored in bone.
CLASS OF JOINT MOBILITY STABILITY EXAMPLES FROM THE SKELETON
DIAGRAM
FIBROUS
NO MOVEMENT
MOST STABLE
Joints between the bones of the
skull and between the
fused bones of the sacrum and
coccyx.
CARTILAGINOUS
LITTLE MOVEMENT
STABLE
Joints between the bodies of
adjacent vertebrae in the
cervical, thoracic and part of the
lumbar spine.
SYNOVIAL
FREE MOVEMENT
LEAST STABLE
Joints between the bones of the
arms and legs
KEY TERMS
DIAPHYSIS
The shaft or middle part of a long bone
EPIPHYSIS
The end portion of a long bone
BONE MARROW
Connective tissue found in the spaces inside bone that is the site of blood cell production
and fat storage.
GROWTH PLATE
The area of growing tissue near the end of long bones in children and adolescents, often
referred to as the epiphyseal plate. When physical maturity is reached, the growth plate
is replaced by solid bone.
ARTICULAR CARTILAGE
A thin layer of glassy-smooth cartilage that is quite spongy and covers the end of bones
at a joint.
JOINTS
Joints are links between the bones of the skeleton. They act to allow movement but also
work to stabilise areas of the body. Consider the action of kicking a football. The Knee of
one leg is allowing the lower part of the limb to swing freely while the knee of the
supporting limb is keeping the leg stable to maintain balance during the execution of the
skill.
REMEMBER
Freely movable joints are located in the limbs of the appendicular skeleton, while
immovable and slightly movable joints are more commonly found in the axial skeleton.
Joints are classified in three ways according to the balance that they allow between
stability and mobility.
EXAM TIPS
As PE specialists, we are mainly interested in joints that allow free movement as they
allow us to perform skills and techniques during physical activity. In preparation for your
exam, be familiar with all classes of joint but focus your study on synovial joints.
SYNOVIAL JOINTS
THE STRUCTURE OF SYNOVIAL JOINTS
Synovial joints have four main distinguishing features, shown and analysed in the table.
FEATURE STRUCTURE FUNCTION
Ligament A band of strong fibrous tissue To connect bone to bone
Synovial fluid A slippery fluid the consistency of egg-whites that is contained within the joint cavity
To reduce friction between the articular cartilage in the joint
Articular cartilage Glassy- smooth cartilage that is spongy and covers the ends of the bones in the joint
To absorb shock and to prevent friction between the ends of the bones in the joint
Joint Capsule A tough fibrous tissue that has two layers, with the fibrous capsule lying outside the synovial membrane
The fibrous capsule helps to strengthen the joint, while the synovial membrane lines the joint and secretes synovial fluid
Ligament
A
P
P
L
Y
KEY TERM
JOINT CAVITY A space within a synovial joint that contains synovial fluid.
REMEMBER
Synovial fluid is also found within the articular cartilage. When the joint is moved
or compressed it seeps out to reduce friction between the cartilages. When
movement stops, the synovial fluid is reabsorbed into the articular cartilage. This is
called the weeping lubrication theory. It suggests that the articular cartilage acts a
little like a sponge in water.
APPLY IT
Discuss the importance of mobilising each of your synovial joints as part of a warm up
routine before physical activity.
As well as the four features in the previous table. Some synovial joints have additional
features which are shown below.
Shoulder joint –bursa
Knee joint – meniscus
Elbow joint – pad of fat
TASK 3
Synovial joints require a fine balance between stability and mobility. From your knowledge
of the general structure of synovial joints:
1. List two features that increase joint stability, giving a specific function for each.
2. List two features that increase joint mobility, giving a specific functionfor each.
TASK 4
Look at the shapes of the articulating surfaces of the types of joint explained in the table
above. Comment on the degree of stability and mobility in each type, giving reasons for
your answer. The information given in Table 4 on page 10 about joint stability might be a
usefulway to check your answers.
KEY TERMS
BURSA
A flattened fibrous sac lines with synovial fluid that contains a thin film of synovial
fluid. Its function is to prevent friction at sites in the body where ligaments,
muscles, tendons or bones might rub together.
MENISCUS
A wedge of white fibrocartilage that improves the fit between adjacent bone
ends, making the joint more stable and reducing wear and tear on joint surfaces.
PAD OF FAT
A fatty pad that provides cushioning between the fibrous capsule and a bone or
muscle.
TYPES OF SYNOVIAL JOINTS
As we have seen, synovial joints have many common structural characteristics. However,
the shapes of the articulating surfaces within the joint capsules vary considerably and this
determines how much movement is allowed at a particular joint.
EXAM TIP
As well as the two synovial joints found in the spine, pivot and gliding, there is also a
cartilaginous joint found between the bodies of the adjacent vertebrae. You will need to
remember all three types of joint found in the spine for your exam and be able to give
examples.
MOVEMENTS OF SYNOVIAL JOINTS
The movements at any particular joint are possibly because of its structure and the skeletal muscles
that contract to pull the bone into a different position. It is important to understand that every
skeletal muscle is attached to bone at a minimum of two points on opposite sides of a joint. When
the muscle contracts across a joint, one point of attachment is pulled towards the other, causing
joint movement.
To allow us to describe the movements of synovial joints during physical activity, it is essential that
we have knowledge of the universally accepted initial reference position. This is the anatomical
position, which is the upright moves the same joint in the opposite direction and are standing
position with the arms by the sides and palms facing forwards. Movements have an accompanying
movement that moves the same joint in the opposite direction and are therefore best listed in pairs.
KEY TERM
PLANES OF MOVEMENT
A flat surface running through the body within which different types of
movement can take place about different types of synovial joint. There are
three main planes that describe the movement of the human body.
APPLY IT
See if you can find out the names and positions of the
three planes of movement.
Explain why the gliding joints and cartilaginous joints in
the in the spine allow only restricted movement in these
planes.
Discuss the potential dangers of forces acting on these
joints that would drive them beyond their normal range
of movement and suggest the types of physical activity
during which this might be more likely to happen.
TYPE OF SYNOVIAL
JOINT
EXAMPLES FROM THE SKELETON
DESCRIPTION MOBILITY
Ball and Socket
Shoulder (head of
humerous with glenoid fossa of
scapula)
A ball shaped head of one bone articulates with a cup like socket of an adjacent bone.
Movement can occur in three planes. This
joint allows the greatest range of movement.
Hinge Elbow Knee Ankle
A cylindrical protusion of one bone articulates with a trough-shaped depression of an adjacent bone.
Movement is restricted to
one plane. This joint allows bending and straightening
only.
Pivot Radio – ular Spine
(atlas/axis at the top)
A rounded or pointed structure of one bone articulates with a ring-shaped structure of an
adjacent bone.
Movement is restricted to
one plane. This joint allows
rotation about its longitudinal
axis only.
Condyloid Wrist Similar to a ball and socket joint but with much flatter articulating surfaces forming a much
shallower joint.
Movement can occur in two planes. This
joint allows the second greatest
range of movement.
Gliding Spine (between the
bony processes of the vertebrae in the cervical, thoracic and part of the
lumbar regions)
Articulating surfaces are almost flat and of a similar size.
Gliding allows movement in three planes,
but it is severely limited.
The following book needs to be purchased for the course. The best price is usually
found on Amazon.
OCR PE AS, Dave Carnell, John Ireland, Ken Mackreth, Clair Miller, Sarah Van Wely. ISBN
No97870435466770
Read the following topics. Acquiring Motor Skills
Classification of Motor Skills and Abilities.
The development of Motor Skills.
Socio Cultural
Surviving Ethic Sports and Games in the UK