Joint Features and Functions GCSE PE Learning objectives

Joint Features and Functions GCSE PE

Learning objectives What we will learn in this lesson: Learning objectives The 3 types of connective tissue and their functions How joints and flexibility are effected by physical activity and age. We will also use this lesson to recap: The types and location of different synovial joints in the body The movement allowed at each synovial joint 2 of 37 © Boardworks Ltd 2006

Starter: Different types of joint

Connective tissues are vital to the functioning of joints. There are 3 types of connective tissue: Tendons connect muscles to bones.

Connective tissues Ligaments are tough, elastic fibres that link bones to bones.

Connective tissues Cartilage prevents the ends of bones rubbing together at joints. Its slippery surface also helps to lubricate the joint.

Tendons and Ligaments are responsible for holding joints together. They prevent bones moving out of position during the stresses of physical activity. If they are pulled or twisted too far by extreme physical movements, ligaments can tear and the joint may dislocate. Using the information above, write 3 bullet points to describe the structure and functions of Ligaments

Tendons and Ligaments Tendons anchor muscles to bones, allowing the muscles to move the skeleton. Tendons are not very elastic –if they were, then the force produced by muscles would be absorbed instead of creating movement. Tendons can also be torn if subjected to too much force. Ligaments and tendons are strengthened by training. Using the information above, write 3 bullet points to describe the structure and functions of Tendons

Tendons and ligaments

Where they lie in Freely movable (synovial) joints The joint capsule is an outer sleeve that protects and holds the knee together. Synovial fluid The synovial membrane lines the capsule and secretes synovial fluid – a liquid Cartilage which lubricates the joint, allowing it to move freely. Smooth coverings of cartilage at the ends of the bones stops them rubbing together and provide some shock absorption. Femur Tibia Synovial membrane Joint capsule Ligaments hold the bones together and keep them in place. Can you label the location of Tendons in this diagram?

Types of synovial joints

Joint movement – how do we move?

Synovial joints – sporting examples During the butterfly stroke, the ball and socket joint of the shoulder allows the swimmer’s arm to rotate. You might head a football using the pivot joint in your neck, which allows your head to rotate. What type of joint allows a handball player’s fingers to spread apart so that they can control the ball with one hand? Answer: Condyloid joints between metacarpals and phalanges 13 of 37 © Boardworks Ltd 2006

Synovial joints – sporting examples The saddle joint allows the thumb to curl around a canoe paddle to give a firm grip. The hinge joint at the knee allows the leg to flex and extend, for example when a hurdler extends their trail leg at take-off and then flexes it as they clear the hurdle. Can you think of a sporting movement that involves the gliding joints between the tarsals? Footballer changing direction – ankle twists sideways slightly 14 of 37 © Boardworks Ltd 2006

Name the bones in these joints 15 of 37 © Boardworks Ltd 2006

Other synovial joints Look at this cricketer making a catch. Elbow: Flexion Task – try to work out the movements at each joint. 16 of 37 © Boardworks Ltd 2006

Sporting movement 17 of 37 © Boardworks Ltd 2006

© EMPICS Ltd Joint and movement analysis Analyse the joint movements involved in these

Joints in action Copy this table onto your sheet and fill in the boxes

Joints and sport Joint flexibility is important in sport, especially in activities like gymnastics and diving that require extreme movements. Participants in all sports however, can benefit from the greater range of movement that comes with improved flexibility. Flexibility exercises increase the range of movement at joints. This can reduce the risk of injury and damage as the joints are more able to absorb forces. However, overstretching joints can cause injury to them. 20 of 37 © Boardworks Ltd 2006

Joints and old age Most people’s flexibility deteriorates as they get older. This is because the connective tissues around the joints become less elastic. Flexibility exercises and extended warm-ups before exercise can help, but ultimately, it becomes harder and harder to maintain the same levels of flexibility. Young gymnasts benefit from good flexibility. Some people, especially older individuals, may develop arthritis – a disease that causes pain, stiffness and inflammation around joints. It is usually hereditary, but injured joints that have not healed properly can be more prone to arthritis. 21 of 37 © Boardworks Ltd 2006

Exam-style questions 1. This diagram shows a cross section of the knee. a) Name bones a, b and c. b a b) Name substance d. 2. c) List the types of movement possible at the knee. d c d) Explain the role of cartilage in the functioning of the knee. 2. Explain how age affects joint flexibility and suggest a way in which flexibility can be improved. 22 of 37 © Boardworks Ltd 2006