Regardless of the kind, every wave has an amplitude. Amplitude is the maximum displacement of points on a wave, which you can think of as the degree or intensity of change. This maximum displacement is measured from the equilibrium position.The picture below shows a diagram of a sine wave.mplitude is an important parameter of waves and is the maximum displacement of points on a wave. Stated another way, amplitude is the vertical distance between a peak or a valley and the equilibrium point. Frequency is the number of wave cycles passing a point per unit time.
Darkfield Digital Image Gallery Dogfish Shark Placoid Scales Dogfish sharks are small sharks belonging to one of three families: the dogfish shark family, Squalidae; the requiem shark family, Carcharhinidae; and the cat shark family, Scyliorhinidae.he green dogfish, along with several other members of the dogfish shark family, is luminescent. Scales are small plates that form part of the skin of certain animals. They provide protection from the environment and from predators. Sharks have placoid scales, bony, spiny projections with an enamel-like covering.
The outer design of sharks and bony fish is also contrasting. 1  Shark skin is covered by dermal denticles, toothlike placoid scales that are covered with enamel. 2  Shark fins are stiff and lack the fine bony spines and muscle control found in teleost. 3  Both sharks and bony fish have caudal fins, or tail fins with two lobes. Bony fish are covered in flat scales, either cycloid, ctenoid or ganoid, that grow as the fish grows. 2  The rings on these scales can be used to estimate age in bony fish, just as you would count the rings on a tree. 3  However, dermal denticles do not grow with the shark so they can not be used in age estimation.