The price elasticity of demand measures thea. responsiveness of a good's price to a change in quantity demandedb. adaptability of suppliers when a change in demand alters the price of a goodc. responsiveness of quantity demanded to a change in a good's priced. adaptability of buyers when there is a change in demande.
Striations are a key attribute to identify skeletal and cardiac muscle types. Although striations are usually visible in most sections of these muscle types, it can sometimes take a little adjustment of the microscope lighting to see them clearly.
The most prominent striations are due to the A bands, the I bands, and the lines of Z discs. The unit between two Z lines is called a sarcomere. In the A band the proteins actin and myosin are both present whereas the I band contains only actin. Above: Diagram of the unit within a muscle cell that is known as a sarcomere.  When muscle contracts the sarcomere shortens and the lines of the Z discs move closer together. For further information: http://muscle.ucsd.edu/musintro/diffraction.shtml features an interesting article about measuring the length of a sarcomere using laser diffraction.