What organelle of skeletal muscle cells stores calcium used in muscle contaction?

Answer: Sacroplasmic recticulum is an organelle in the muscle cells that stores calcium used in muscle contraction.

Explanation:

Muscle contraction is the activation of sites in the muscle fibres that produce tension. It does not necessary means muscle shortening as tension can be generated without any change in muscle length.

Sacroplasmic recticulum is similar to endoplasmic recticulum and its is an organelle in the muscle cells that stores calcium needed for muscle contraction. It contains the ion channels pump that are responsible for pumping calcium into the sacroplasmic recticulum.