Unreasonable Results (a) What resistance would you put in parallel with a 40.0- galvanometer having a 25.0-A sensitivity to allow it to be used as an ammeter that has a full-scale deflection for 10.0-A ? (b) What is unreasonable about this result? (c) Which assumptions are responsible?
Lecture objectives 15 Neuromuscular transmission 1. How does the movement of the myofibrils lead to muscle contraction Myosin head attaches to actin, ADP and P are released as myosin head pivots, moving to a low energy state. It pulls the actin filament with it towards the M line. ATP attaches to myosin, releasing it to the myosin head from the actin. As ATP is hydrolyzed to ADP and P the myosin head return to the pre stock high energy cocked position. 2. Describe and identify the motor unit A motor unit is made up of a otor neuron and the skeletal muscle fibers innervated by that otor neuron's axonal terminals. Groups of otor units often work together to coordinate the contractions of a single muscle. A single branch motor neuron only contact a single muscle fiber. 3. What are the anatomical structures needed for muscle contraction Not answering specifically, found in all other answers. 4. ***Describe in detail the 3 phases of muscle contraction Phase 1 Neuromuscular Junction Stimulation Action potential arrives at the axon terminal of motor neuron. Voltage-gated Ca2+ channels open allowing Ca2+ which allows ACh to be released into the synaptic cleft via exocytosis. Ach then binds to reception on the sarcolemma/on junctional fold of the sarcolemma. ACh opens ion channels (nonselective monovalent cation receptors) that allow Na+ to enter the cell and K+ to exit the cell simultaneously. More Na+ goes in then K+ goes out which causes local change in membrane potential called the end plate potential. Termin