Rice Home work: The Muscle System Due at the start of class P. 408 Excitability are plasma membranes that can change their electrical state and send electrical wave called an action along the entire length of the membrane. Contraction smooth muscle activates enzymes, which in turn activates myosin heads, and they all relax when Ca++ is removed and the actin-binding sites are re-shielded. P. 410 Muscle fibers are organized into individual bundles are called fascicle. A middle layer of connective tissue is called perimysium. Inside each fascicle, each muscle fiber is encased in a thin connective tissue layer of collagen and reticular fibers called the endomysium. The mysia may fuse with a broad, tendon-like sheet called aponeurosis, or to fascia, the connective tissue between skin and bones. P. 411 The plasma membrane of muscle fibers is called the sarcolemma, the cytoplasm is referred to as sarcoplasm, and the specialized smooth endoplasmic reticulum, which stores, releases, and retrieves calcium ions is called the sarcoplasmic reticulum. P. 411. During the contraction, the thin filaments slide past the thick filaments. The thick filaments are the myosin and the thin filaments are called actin. Both do contract and relax. P. Twitch is a single connection potential from a motor neuron will produce a single contraction in the muscle fibers of its motor unit. Treppe results in greater tension, and it results from simulating the muscle before it has a chance to relax. Tetanus is prolonged contraction without relaxation and results from repeating stimulation before the muscle has a chance to relax. For Pre AP only: In ADDITION to the work above, describe the action potential of the muscle, starting on page 413 to page 422. Be sure to describe the ions involved in muscle contraction, what occurs during the sliding filament theory, power stroke and the involvement of ATP and ADP, glycolysis, pyruvic acid and lactic acid. Action potential is the action of the nerve sending the signal to the muscle fiber, there the fiber helps the muscle contract. Meaning the fibers are “organized into units sarcomeres.” These contain two specific types of filaments being: (1) myosinthick filament and (2) actin- thin filament. When the sacromeres recive the action potential signal and will lead to the two filaments to come together, creating a cross bridge which is result the release of calcium ions. ALL WORK IN YOUR OWN WORDS. NEVER COPY AND PASTE AN AUTHOR’S WORK WITHOUT THEIR WRITTEN CONSENT OR WITHOUT CITATION. YOU KNOW THAT THIS IS CALLED PLAGIARISM. ALL ANSWERS IN YOUR OWN WORDS.