Muscle contraction (sarcomere)

Learning objectives

To understand the relationship between the structure of a sarcomere and its function.
To clarify the principle stages of muscle contraction.
To bring out the relationship between the shrinking of I bands and the sliding of myofilaments.

This animation presents muscle contraction at the level of the sarcomere by providing an animated schematic diagram in parallel with corresponding electron micrographs taken using a transmission electron microscope (TEM).
Photos: © James E. DENNIS - PHOTOTAKE - ISM.