Muscle

Thick filaments within the sarcomere of a muscle fiber. Consisting of (myosin tail, hinge, head) which may result in head swings toward or away from the M(middle) line effecting the width of the H zone.

Acetylcholine is a neurotransmitter, a chemical released by a neuron to change the permeability or other properties of another cell membrane.

An enyzme found in the synaptic cleft, bound to the postsynaptic membrane, and in tissue fluids; breaks down and inactivates ACh

Calsequestrin is a calcium-binding protein of the sarcoplasmic reticulum. The protein helps hold calcium in the cisterna of the sarcoplasmic reticulum after a muscle contraction, even though the concentration of calcium in the sarcoplasmic reticulum is much higher than in the cytosol. It also helps sarcoplasmic reticulum store an amazing amount of calcium ions.

A myosin head that projects from the surface of a thick filament and that can bind to an active site of a thin filament in the presence of calcium ions.

A delicate network of connective tissue fibers that surrounds individual muscle cells.

A dense layer of collagen fibers that surrounds a skeletal muscle and is continuous with the tendons/aponeuroses of the muscle and with the perimysium.

The link between the generation of an action potential in the sarcolemma and the start of a muscle contraction.

A twisted strand composed of two rows of 300-400 individual globular molecules of G actin; held together by "nebulin".

Molecules (subunits)within the F actin strand; wrapped around nebulin.