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.
Scales vary enormously in size, shape, structure, and extent, ranging from strong and rigid armour plates in fishes such as shrimpfishes and boxfishes, to microscopic or absent in fishes such as eels and anglerfishes. The morphology of a scale can be used to identify the species of fish it came from. Cartilaginous fishes (sharks and rays) are covered with placoid scales. Most bony fishes are covered with the cycloid scales of salmon and carp, or the ctenoid scales of perch, or the ganoid scales of sturgeons and gars. Some species are covered instead by scutes, and others have no outer covering on the skin.