The T tubules store Ca2 . provide a means of rapidly transmitting the action potential from the surface into the central portions of the muscle fiber. store ATP. run longitudinally between the myofibrils. have expanded lateral sacs.

provide a means of rapidly transmitting the action potential from the surface into the central portions of the muscle fiber

Explanation:

T-tubules or Transverse tubules are the tube-like structures present in the muscle fibers.

The T tubules are formed by the modification in the plasma membrane of the cell and therefore arise from the surface of the muscle cell.  The T tubules then pass through the muscle and enter the inner core of the muscle that is near to the sarcoplasmic reticulum.

The main function of the T tubules is to carry forward the action potential from the synaptic junction to the muscle where it triggers the release of the calcium from the muscle.

Thus, the selected option is correct.

good thing- during decomposition the organic molecules in organic matter are broken down into simpler organic molecules that require further decomposition or into mineralised nutrients

bad thing- it can be harmful in crop productivity

a scenario where a cell may be needed to perform a form of endocytosis is when transporting large molecules. a scenario where a cell may be needed to perform a form of exocytosis is when releasing the large molecule from the cell.