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neurologyYou need to know

• The skeletal system supports the body, maintains posture, protects vital organs, provides attachment points for muscles, acts as a system of levers, stores minerals and produces blood cells in bone marrow.
• The axial skeleton consists mainly of the skull, vertebral column, ribs and sternum, while the appendicular skeleton consists mainly of the shoulder girdle, arms, pelvic girdle and legs.
• Major bones used when analysing movement include the cranium, vertebral column, clavicle, scapula, sternum, ribs, humerus, radius, ulna, pelvis, femur, patella, tibia, fibula, carpals, metacarpals, phalanges, tarsals and metatarsals.
• A joint is the place where two or more bones meet, and joints may be fibrous, cartilaginous or synovial depending on their structure and permitted movement.
• Synovial joints contain articular cartilage to reduce friction, synovial fluid to lubricate the joint, a joint capsule for stability and ligaments that connect bone to bone.
• Tendons connect muscle to bone and transmit muscular force, whereas ligaments connect bone to bone and help stabilise joints.
• Hinge joints, such as the elbow and knee, mainly permit flexion and extension, while ball-and-socket joints, such as the shoulder and hip, permit movement in several directions including rotation and circumduction.
• Flexion decreases the angle at a joint, extension increases it, abduction moves a body part away from the midline, adduction moves it towards the midline, and rotation turns it around an axis.
• Dorsiflexion brings the toes towards the shin, plantar flexion points the toes away from the shin, and circumduction combines flexion, extension, abduction and adduction in a circular movement.
• Movement in the sagittal plane occurs forwards or backwards around a transverse axis, movement in the frontal plane occurs sideways around a sagittal axis, and movement in the transverse plane involves rotation around a longitudinal axis.
• Major skeletal muscles include the deltoid, pectoralis major, latissimus dorsi, biceps brachii, triceps brachii, abdominals, erector spinae, iliopsoas, gluteus maximus, quadriceps, hamstrings, gastrocnemius and tibialis anterior.
• Muscles work in antagonistic pairs because they can pull but cannot push, so the agonist contracts to produce a movement while the antagonist relaxes or lengthens to allow it.
• An isotonic contraction produces movement and includes concentric contractions, in which a muscle shortens under tension, and eccentric contractions, in which a muscle lengthens under tension.
• An isometric contraction produces tension without a change in muscle length or joint angle, such as holding a fixed position.
• A motor unit consists of one motor neurone and all the muscle fibres that it controls, and smaller motor units allow finer control while larger motor units produce greater force.
• When a nerve impulse reaches the end of a motor neurone's axon, a neurotransmitter called acetylcholine is released and binds to receptors on the muscle fibre's motor end plate.
• If nervous stimulation reaches the threshold, an action potential spreads across the muscle fibre and causes it to contract according to the all-or-none law.
• Force increases through motor unit recruitment, in which the nervous system activates additional motor units, and through an increased frequency of nerve impulses.
• Slow oxidative fibres have many mitochondria, a dense capillary supply and high aerobic capacity, so they contract slowly, produce relatively low force and resist fatigue.
• Fast oxidative glycolytic fibres produce moderately high force using aerobic and anaerobic energy pathways, while fast glycolytic fibres produce the greatest force through anaerobic pathways but fatigue rapidly; recruitment generally progresses from slow oxidative to fast oxidative glycolytic and then fast glycolytic fibres as exercise intensity rises, with slow oxidative fibres predominating during low-intensity exercise and active recovery.

• Identify the major bones, skeletal muscles and synovial joints accurately on diagrams of the human body.
• Classify a joint movement as flexion, extension, abduction, adduction, rotation, circumduction, dorsiflexion or plantar flexion from a description or sporting example.
• Determine the plane and axis of a sporting movement by relating its direction to the sagittal, frontal or transverse plane.
• Analyse each phase of a sporting action by naming the joint, joint movement, agonist, antagonist and type of muscular contraction.
• Distinguish concentric, eccentric and isometric contractions by deciding whether the active muscle shortens, lengthens or remains the same length under tension.
• Explain the sequence of nervous stimulation from an action potential travelling along a motor neurone to neurotransmitter release at the motor end plate and contraction of the muscle fibres.
• Compare slow oxidative, fast oxidative glycolytic and fast glycolytic fibres using their force production, contraction speed, energy pathways, mitochondrial density and resistance to fatigue.
• Predict which muscle fibre types will be recruited during exercise and active recovery by considering the intensity, duration and force demands of the activity.
• Construct an extended exam response that applies accurate anatomical terminology and evidence from a named physical activity to explain movement and muscular contraction.