Chapter 8: Muscle

Skeletal muscle makes movement, brearning, speech facial expressions possible. Completely voluntary control Excitability: muscle cells produce AP Contractility: muscle cels can shorten Extensiollity, muscle calls can be Stretched or lengenenca Elasticity: musare cous wis return to their og length after being stretened. muscle fiber: individual muscle cell bone fascicles: bundles of muscle fibers tendon fascia, nolac fascicles blood/ncrues together tendon, connects muscle to bone Fascia fascich fiber MUSCIS motor unit consists of one motor neuron all the individual muscle cells it controls Recruitment activation of additional motor units so I musck Strength force of contraction Fatigue: not being able to sustain an expected force from a muscle Central Fatigue, caused by the CNS psychological mechanisms. Peripheral Fatigue problems with the neuromuscular junction between the motor nerve muscle or problems within th muscle cell out the level out the Sacramere Grip force amount of force that can be maintained by squeezing an object as hard as possible isomeric contraction: muscle contracts but there is no movement muscle stays the same length. Eccentric contraction: muscle contracts rengthens concentric contraction: muscle contracts Inorreng Antagonistic pairs muscles mat act on opposite sides of a joint Agonist pairs prime mover muscle that performs the desired action. Antagonist muscle that is capable of opposing action. Coactivation, when motor unies in bath the agonist the antagonist are active out the same time Fisxion & the angle between body parts Extension: the angle between adjacent bady parts. Abduction movement of Dody part away from midiine Aaduction movement of body part toward midline