4JointsAlso called articulations or arthrosisTwo or more bones contact each otherProvide mobilityDetermine the type or range of motion of a particular area of the body
5Bones Are organs Provide a framework to support the body Protection of soft tissue and organsAct as levers for body movementForm blood cells in the bone marrowAllow storage of minerals – calcium and phosphorusBone to bone connection by ligamentsStrengthen jointProvide stability
6Muscles and Tendons Tendons – cords of dense connective tissue Connect muscles to boneMuscles – provide force for movement by shortening the length of their fibers (cells)Muscles only move by contracting fibersMost muscles occur as antagonistic pairs
7Nerves Sensory nerve endings housed in ligaments Allow for monitoring of the position of the jointsHelp prevent over-extension of the joint and it parts
811.2.2Label a diagram of the human elbow joint, including cartilage, synovial fluid, joint capsule, named bones and antagonistic muscles (biceps and triceps).
1111.2.3Outline the functions of the structures in the human elbow joint named in
12Joint PartFunctionCartilageReduces friction & absorbs compressionSynovial fluidLubricates to reduce friction & provides nutrients to the cells of the cartilageJoint capsuleSurrounds the joint, encloses the synovial cavity, & unites the connecting bonesTendonsAttach muscle to boneLigamentsConnect bone to boneBiceps muscleContracts to bring about flexions of the arm (reduce an angle)Triceps muscleContracts to cause extension of the arm (increase an angle)HumerusActs as a lever that allows anchorage of the muscles of the elbowRadiusActs as a lever for the biceps muscleUlnaActs as a lever for the triceps muscle
13Compare the movements of the hip joint and the knee joint
14Ball and Socket Joints The hip is ball and socket joint Permits movement in several directions, including rotational movementHead of femur (ball) fits into acetabulum (depression) of the hip
19Comparing hip & knee joints Hip JointKnee JointFreely moveableAngular motions in many directions and rotational movementsAngular motion in one directionMotions possible are flexion, extension, abduction, adduction, circumduction, and rotationMotions possible are flexion and extensionBall-like structure fits into a cup-like depressionCovex surfac fits into a concave surface
2011.2.5Describe the structure of striated muscle fibres, including the myofibrils with light and dark bands, mitochondria, the sarcoplasmic reticulum, nuclei and the sarcolemma.
2711.2.7Explain how skeletal muscle contracts, including the release of a=calcium ions from the sarcoplasmic reticulum, the formation of cross-bridges, the sliding of actin and myosin filaments, and the use of ATP to break cross-bridges and re-set myosin heads.