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 Chondrichthyes are the cartilaginous fishes including the sharks, rays, skates and chimaeras. The Osteichthyes are the bony fish. Both of these groups became established d â¦ uring the Devonian Period about 400 million years ago.The Chondrichthyes differ from the Osteichthyes in many respects, including their skeletons, scales, teeth, buoyancy, swimming, gills and reproduction. Scales:   Cartilaginous fish have large scales called placoid scales. These have a bone like base embedded in the skin and a backward projecting enamel covered dentine spine. The whole thing has a central pulp cavity (rather like the structure of teeth). The epidermis and dermis form placoid scales.