GCSE Physical Education

The Skeletal System

Part 1 – The structure of the skeletal system

Objectives…1. To be aware of the bones that make up the skeletal system.2. To consider the particular functions that the skeletal system performs.

Part 2 – The role of the skeletal system

Objectives…1. To be aware of how movement occurs through joints.2. To consider the types of movement that are possible because of the skeletal

system.

Functions of the skeleton

The skeleton performs many functions in the body.

Shape – The skeleton gives us our shape and determines our size.

Blood cell production – blood cells are made in the bone marrow.

Movement – The skeleton allows us to move. Muscles are attached to the bones and move them as levers.

Protection – The skeleton protects delicate parts of the body like the brain and lungs.

Support – The skeleton supports muscles and organs.

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Shape and Size

SupportThe skeleton acts as a framework.

It gives the body support, enabling us to stand and walk upright.

The bones of the back and chest support internal organs and help to keep them in place.

The bones of the body are held together by ligaments.

The skeleton provides a framework for the muscles, which are attached to bones by tendons.

Can you imagine what humans would look like if they didn’t have bones to support them?

MovementBones work with muscles to produce movement.

Muscles are attached to bones by tendons.

Bones have surfaces that allow for strong attachment. Tendons fuse with the tough Periosteum membrane on the outside of the bone.

Muscle

Tendon

Periosteum

Bone

Movement

ProtectionSome of our body parts, such as the brain, are very delicate and need protection from external forces.

Bones can protect body parts from impacts and injuries.

The cranium protects the brain. It encloses the brain entirely in a shell of bone.

The rib cage protects the delicate organs of the chest.

Can you think of two reasons why the rib cage has gaps in it rather than being a solid shell of bone?

cranium

Blood cell productionRed and white blood cells and platelets are made in the bones.

The ends of long bones and some other bones including the ribs, humerus, femur and even vertebrae bones, contain red bone marrow.

This is where the blood cells are produced.

The shaft of long bones is filled with yellow bone marrow which does not produce blood cells.

Red marrow embedded in spongy bone

Yellow bone marrow in the shaft

Cranium (skull)

Sternum (breast bone)

Ribs

Ilium (part of the pelvis)

Humerus

Ulna

Radius

Femur

Patella (knee cap)

Tibia

Fibula

Clavicle (collar bone)

Naming bones

Scapula (shoulder blade)

Vertebral column (spine)

Carpals

Metacarpals

Phalanges

Tarsals

Metatarsals

FOOT

HAND

Naming bones

Naming bonesQuick TEST – try to do it without looking at your notes

Classification of bones – long bones

Long bones have a long shaft.

They are responsible for a lot of movement.

Long bones include the femur, humerus, tibia, fibula, the metatarsals, metacarpals and phalanges.

Long bones contain red bone marrow for producing blood cells.

Long bone

Classification of bones – flat bones

Flat bones perform a variety of functions. These include:

They have a large surface area.

protection for delicate areas, for example, the cranium protects the brain.

areas for muscle attachment.Cranium

Classification of bones – short bones

Short bones are very light and very strong.

They are small and squat in shape.

The carpals in the wrist and the tarsals in the foot are examples of short bones.

carpals

tarsals

Classification of bones – irregular bones

Irregular bones are specially shaped to perform a particular function.

Examples include the patella and the vertebrae.

The patella is shaped so that the quadriceps tendon slides

easily over the knee joint.

patella

Bones and joint movements

GCSE Physical Education

The Skeletal System

Part 1 – The structure of the skeletal system

Objectives…1. To be aware of the bones that make up the skeletal system.2. To consider the particular functions that the skeletal system performs.

Part 2 – The role of the skeletal system

Objectives…1. To be aware of how movement occurs through joints.2. To consider the types of movement that are possible because of the skeletal

system.

Main types of Joint

• Immovable – no movement allowed (bones of the cranium)

• Slightly Moveable – a good example is the Joint between the vertebrae

• Freely moveable – also called Synovial• Ball and Socket• Hinge• Pivot• Gliding• Saddle• Condyloid

Movement

Movement Our joints allow us to move in a number of different ways

– Flexion – the decrease of an angle between two bones at a joint (bending a limb)

• Eg. ‘Flexing’ your arm when doing a bicep curl in the gym

– Extension – The increase of an angle between two bones at a joint (straightening a limb)

• Eg. At the point of contact with a football the leg is extended

– Abduction – taking a limb away from the centre line of the body• Eg. When stepping out to play a shot in badminton the leg is abducted

– Adduction – Bringing a limb back in towards the centre line of the body• Eg. When hitting a forehand tennis stroke, after contact the arms comes back

to the centre line of the body

– Rotation – where a bone turn on its axis• Eg. When turning the head to look sideways the pivot joint in the neck is

allowing rotation

Ball and Socket Joint – such as the hip

• Movement allowed– Flexion– Extension– Rotation– Adduction– Abduction

Hinge Joint – such as the elbow

• Movement allowed– Flexion and Extension

only

Elbow

Pivot Joint – such as the neck

• Allows rotation only• Is found in the neck

where the atlas and axis work to allow to turn our heads

Gliding Joint – such as the bones in the hand

• These joints glide across each other to allow slight flexion, extension, adduction, abduction

• Gliding joints have flattened or curved faces. • Good examples are the carpal and tarsal bones in the

wrist and foot

Saddle Joint – such as the thumb

• These joints have one surface that is convex and the other is concave.

• These joints allow flexion, extension, adduction, abduction but no rotation

Condyloid Joint – such as the wrist

• These joints appear as a ‘shallow saddle’• These joints allow flexion, extension, adduction,

abduction

Tendons

The role of a tendon is to attach muscle to bone so that when a muscle contracts it moves the bones

Ligaments and Cartilage

• Ligaments Attach bone to bone

– Tough fibrous straps– They provide stability to the joint– They help to prevent injury

• Cartilage Found between the ends of bones

• Smooth shiny surface• Prevents friction• Protects bone surface