Bones: Provide a firm anchorage for muscles. They also act as levers, changing the size or direction of forces generated by muscles.
Ligaments: connect bone to bone, restricting movement at joints and helping to prevent dislocation.
Muscles: The muscles provide the force necessary for movement by shortening the length of their fibres or cells.
Tendons: attach muscle to bone
Nerves: stimulate muscles to contract at a precise time and extent, so that movement is co-ordinated.
11.2.2 label a diagram of the human elbow joint, including cartilage, synovial, fluid, joint capsule, named bones and antagonistic muscles (biceps and triceps)
11.2.3 Outline the function of the structures in the human elbow joint named in 11.2.2
Junctions between the bones are called joints.
Cartilage reduces friction between bones where they meet
Synovial fluid lubricates the joint to reduce friction
Joint capsule seals the joint and holds in the synovial fluid
11.2.4 compare the movement of the hip joint and the knee joint
The knee is a hinge joint; it allows considerable movement in one plane; bending (flexion) or strengthening (extension) but little movement in other two planes. In contrast, the hip joint allows movement in three planes (protraction/retraction, abduction/adduction and rotation).
11.2.5 Describe the structure of striated muscles fibres, including the myofibrils with light and dark bands, mitochondria, the sarcoplasmic reticulum, nuclei and the sarcolemma.
When viewed under a light microscope skeletal muscle is seen to consist of large multinucleate cells called muscle fibres. Within each muscle fibre are cylindrical structures called myofibrils. The myofibrils consist of repeating units called sarcomeres, which have light and dark bands. The light and dark bands extend across all the myofibrils in a muscle fibre, giving it a striated...