*Objectives in bold, notes from the text following.
The structure, role, and function of skeletal muscle
--Skeletal muscle accounts for 35-45% of total
body weight and is comprised of 600 different muscles
--Muscles usually work in groups to produce bodily movement, the
agonist initiating a desired movement and the
antagonist stretching to stop or slow the movement.
--Muscles are elastic, extendable, and contactable--they can shorten to nearly 50% of their resting length and stretch up to 150% of their resting length.
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Concentric Action: when a muscle overcomes a load and shortens, as in the upward phase of a biceps curl exercise.
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Eccentric Action: when a muscle can't develop sufficient tension and is overcome by an external load and progressively lengthens; walking down stairs involves an eccentric action of the quadriceps muscle group as it decelerates the the flexion action of the knee.
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Isometric Action: when a muscle generates force against a resistance but does not overcome it and therefore doesn't shorten, lengthen, or cause joint movement; many of the
body's posture muscles work isometrically to hold or restrain the skeleton in an upright position in opposition to the force of gravity.
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Muscle fiber: the structural component of skeletal muscle-a cylindrical cell containing hundreds of nuclei
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Endomysium: layer of connective tissue that surrounds the muscle fiber and and separates the fibers from each other
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Fascicles: bundles of up to 150 muscle fibers
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Perimysium: connective tissue surrounding the fasciculus
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Epimysium: a dense protective sheath of connective tissue surrounding the entire muscle, forming a strong connective tissue of tendons that fasten to the outermost covering of bone
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Periosteum: outermost covering of bone
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Sarcolemma: thin plasma membrane surrounding each muscle fiber, under the endomysium, and it conducts an electromagnetic wave of depolarization along the surface of the muscle fiber. Also serves to insulate muscle fibers from one another during the depolarization occurrence. Also fuses with the endomysium
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Satellite Cells: found within the basement membrane of the sarcolemma and have important regulatory functions for cellular growth.
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Sarcoplasm: fluid resembling gelatin found in the spaces within the muscle fiber; contains lipids (fat), glycogen, enzymes, nuclei, mitochondria, and other cellular organelles. Sarcoplasm is analogous to cytoplasm in other cells, but is a storage site for large amounts of glycogen (for
energy utilization) and myoglobin (for oxygen binding).
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Transverse Tubules: extensions of the sarcoplasm that pass through the muscle fiber and serve as transport vesicles for certain substances, such as ions, oxygen and glucose.
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Sarcoplasmic Reticulum: Highly specialized complex within the muscle fiber that stores calcium ions; longitudinal system of tubules.
* Damn I am so glad I remember a lot of things I learned from high school physiology class--although I think it was endoplasmic reticulum that I learned about! Good thing I got an A in that class! 
