T or F

A. True

There are actually several aspects of smooth muscle contraction that will reduce the need for ATP.  First off, since the S.R. is so much less developed in smooth muscle, there are many fewer Ca-ATPase molecules on its membrane.  Smooth muscle makes up the difference by using the ATPases on its cell membrane to send the Ca++ into the extracellular fluid.  Therefore, the energy usage by the two ATPases is about equivalent to the ATP use by the Ca-ATPase on the skeletal muscle S.R.   That takes care of part of the ATP load, but we still have that extra ATP hydrolyzed by the MLCK.  This contributes nearly 1 ATP per cycle in addition to the one ATP used by the myosin ATPase.  It still seems that the smooth muscle cell is using more energy, not less to produce contraction.