BIOL 150 Chapter Notes - Chapter 48: Myosin Head, Myofibril, Neuromuscular Junction
Document Summary
One contracts while other relaxes (opposite muscle functions) articulation - -joint. Place where two skeletal elements meet (bones, cartilage) Hinge joints hinge contraction - -calcium is needed for contraction. Connective tissue exoskeleton - on the outside of the body, usually hollow structures that cover the outside of the body extensor - for relaxation of bone (quadriceps) fast fiber - -white. Low myoglobin concentration flexor - bring two bones closer together (hamstring) how action potentials trigger muscle contraction (steps) - -action potential arrives, and releases acytocolene. Aceytocoline binds to acetocline receptors that are on the muscle cell. Enough is released to cause an action potential in the muscle cell (muscle cell has t tubules) action potential can propagate down t tubule. T tubule is closesly associated with sarcoplasmic reticulum, allow action potential to infultrate into the muscle cell. Causes calcium channels to open into sarcoplasmic reticulum.
