11. It is composed of a single T-tubule paired with a terminal cisterna of the sarcoplasmic reticulum . 12. The L-type calcium channels are in close association with ryanodine receptors present on the sarcoplasmic reticulum . 13. While the muscle fiber does not have a smooth endoplasmic reticulum, it contains a sarcoplasmic reticulum . 14. The Ca2 + flows from the sarcoplasmic reticulum into the sarcomere with both of its filaments. 15. It is composed of a single t-tubule paired with a terminal cisterna of the sarcoplasmic reticulum . 16. Calcium is released from the sarcoplasmic reticulum into the sarcomere when a muscle is stimulated to contract. 17. The action potential then travels along T ( transverse ) tubules until it reaches the sarcoplasmic reticulum . 18. Cardiac muscle forms these instead of the triads formed between the sarcoplasmic reticulum in skeletal muscle and T-tubules. 19. IP 4 does not stimulate calcium influx through IP 3 receptor channels on the endoplasmic or sarcoplasmic reticulum . 20. The active pumping of ions into the sarcoplasmic reticulum creates a deficiency in the fluid around the myofibrils.
