Option B Muscles and Fitness
Movement in Humans Muscles: provide the force needed locomotion Tendons: attach muscle to bone Bones: provide an anchor for muscles, act as levers changing the size or direction of forces generated by muscles Ligaments: connect bone to bone, restricting movement at the joint Nerves: stimulate and coordinate muscle movement
Sliding Filament Theory of Muscle Contraction Relaxed vs. Contracted Sarcomere
Synaptic Transmission
Physiology of Muscle Contraction Animation: Action Potentials and Muscle Contraction
(Knee) Joint: junction between bones Cartilage – reduces friction; Synovial Fluid – lubrication; Joint Capsule – seals the joint, holds in the synovial fluid Ligaments
Joint Injuries Sprains Grade I, II, III
Grade I sprain: pain with minimal damage to the ligaments. Grade II sprain: massive ligament damage and mild looseness of the joint. Grade III sprain: the ligament is completely torn and the joint is very loose or unstable.
Torn Muscle
Joint Dislocation: bones moved out of alignment; often accompanied by ligament damage
Intervertebral Disc Damage: bulging disc presses on nerves causing radiating pain