ANATOMY 1 Lecture Notes - Lecture 12: East Los Angeles College, Sliding Filament Theory, Endoplasmic Reticulum
Document Summary
Sarcolemma: delicate elastic sheath/plasma membrane covering striated muscle fibers. T-tubules: deep invaginations of the sarcolemma of skeletal or cardiac muscle fibers that surround myofibrils; involved in transmitting the action potential from the sarcolemma to the interior of the myofibril. Sarcoplasmic reticulum (sr)=ser with ca2+; the specialized endoplasmic reticulum of cardiac muscle and skeletal striated muscle that functions especially as a storage and release area for calcium. M line: fine line in the center of the a band of the sarcomere of striated muscle myofibrils. Mechanism of muscle contraction based on muscle proteins that slide past each other to generate movement; the binding of myosin to actin, forming cross-bridges that generate filament movement. Sequence of depolarizations and repolarizations propagate along excitable. Membrane=more negative on the inside, more positive on the outside at rest. Resting membrane potential: of a neuron is about -70 mv (mv=millivolt) - this means that the inside of the neuron is 70 mv less than the outside.
