In Your Own Words, Briefly Define "Material Circumstances" and "Historic

question 22

Essay

In your own words, briefly define "material circumstances" and "historic situations."

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Definitions:

Terminal Cisternae

Enlarged areas of the sarcoplasmic reticulum surrounding the transverse tubules in muscle cells, involved in calcium storage and release.

Sarcoplasmic Reticulum

A specialized type of smooth endoplasmic reticulum found in muscle cells, involved in the regulation of calcium ions.

H-band

A region within the sarcomere of striated muscle fibers that shortens during muscle contraction and is situated between the filaments of actin and myosin.

Glycerinated Muscle Fibers

Muscle fibers treated with glycerol to remove cellular contents while preserving the structure, used in experiments to study muscle contractions.