1. NERVE STIMULUS & POTENTIAL ACTION KAYLEE SERRANO, ALANNA HAAG, JESSICA DELGADO, TYLER BRYON, MEGHAN MUNIZ – PERIOD 2

2. PAGE 189 -One motor neuron may stimulate a few muscle cells or hundred of them, depending on the particular muscle and the work it does. -One neuron and all the skeletal muscle cells it stimulates are a motor unit. -When a long, threadlike extension of the neuron, called the nerve fiber or the axon, reaches the muscle it branches into a number of axon terminals. Each of which forms junctions with the sarcolemma of a different muscle cell.

3. MOTOR UNIT

5. PAGE 190 -Excess of positive ions reverses electrical conditions of the sarcolemma and opens more channels for only Na+ to enter thus resulting in action potential. -Action potential is ‘ upset’ generated electrical current. -Has unstoppable motion -Travels along the entire sarcolemma.

6. -The result of its electrical charge is the muscle contracting. -While action potential is occurring, acetylcholine, which began the process is broken down to acetic acid and choline by enzymes present on the sarcolemma. -Because of this, a single nerve impulse produces only one contraction. -This prevents continued contraction without nerve impulses.