The sarcoplasmic reticulum is an elaborate network of membranes in skeletal muscle cells that functions in calcium storage. This structure is essentially a modified:

Saltatory conduction is made possible by:

Graded potentials travel down the membrane via ___________ propagation.

With myasthenia gravis:

Identify the hair matrix.

Identify the papillary layer.

Although the integument is a covering, it is by no means simple, and some of its functions include ________.

Articulations permitting only slight degrees of movement are:

Only dermal portion of the hair.

Which hormone reduces the amount of calcium ions in the bloodstream?