The Body

Structure and Function

The Skeleton

The skeleton is the framework of bones which gives shape and support to the body. It also protects the internal organs like the heart and lungs.

Joints

Where two or three bones meet, we have joints. These allow the skeleton to move. The body has two types of joint which allow free movement.

• Ball and socket joints are found at the shoulder and the hip and allow movement in three dimensions, or directions.

Hinge joints are found at the elbow and at the knee and allow movement in one dimension, or direction.

Examples

Activities that need ball and socket joint

Swimming – pulling action

Badminton – hitting action

Football – kicking action

Activities that need hinge joint

Basketball – shooting, passing

Long jump – take-off, hitch kick

Circuit training – chin-ups, press-ups

Muscles

Skeletal muscles create movement in our bodies.

The muscles which control the movement of the elbow, are the tricep and the bicep.

The bicep contracts or shortens, pulling the lower arm up, and causing the elbow to bend. At this time the tricep relaxes or lengthens. To straighten the elbow it is then the tricep which contracts or shortens in order to pull the lower arm down, and at this time the bicep relaxes.

If we look at the knee we can see the hamstring and the quadricep controlling the movement. The hamstring contracts, pulling the lower leg up and causing the knee to bend. At this time, the quadricep relaxes. To straighten the knee, the quadricep contracts, and pulls the lower leg down. At this time the hamstring is relaxed.

Connective tissue

Connective tissue refers to other features which support the body and its movement.

TENDONS• Strong strips which attach

the muscles to bones. • Muscle contracts to move

a joint, it is the tendon which pulls on the bone.

Connective Tissue cont

LIGAMENTS • Strong bands which

connect bones at the joint.

• Elasticated allow movement

• Strong enough to stop movement outside the normal range.

Connective Tissue cont

CARTILAGE

• Soft cushioning substance which covers the ends of the bones.

• Shock absorber • Reduces the rubbing

of the bone surfaces.

Here's an example of a question you might be expected to answer in your exam and how you

might answer it.

Actions in many activities require movement from either the hinge joint of the knee or elbow. Select an activity. Name a skill/technique and the main hinge joint used.

Muscles, tendons and bones work together to produce the movement for this skill/technique.

Describe the movement required for the skill/technique chosen. Describe how this movement is produced.

Example Answer• Activity - Basketball• Skill/Technique - Lay up• Joint - Knee• Description of movement required:- My left leg

bends then straightens quickly to allow me to jump in the air

• Description or how movement is produced:-• My hamstring contracts pulling on the tendon

connected to the lower leg. This causes my knee to bend. My quadriceps then contract pulling on the tendon to straighten my legs as I jump