peripheral motor neuron. Etymology: Gk, periphereia + L, motor, mover; Gk, neuron, nerve. an effector neuron located outside the central nervous system, usually in a ganglion of the sympathetic or parasympathetic nervous system.
Gneiss rock is further characterized by its alternating light and dark bands of minerals. Gneiss forms from volcanic rock, shale, or granitic. Quartz is typically abundantly found in gneiss. The bands that form on gneiss rock are due to the various rocks that are a part of its make-up. The use of the word gneiss dates back to the mid-1700s. Gneiss rocks that originate as sedimentary rock are called paragneiss and those originating as igneous rock are called orthogneiss. Limestone can change into calcareous gneiss which contains calcium carbonate.
Each kind of sedimentary rock turns into a different kind of metamorphic rock-limestone turns into travertine or marble, and shale turns into slate, and sandstone turns into quartzite.Even though slate is a metamorphic rock, it still looks a lot like a sedimentary rock-it is still in thin layers. A raw (uncut) diamond.hen sedimentary rocks like limestone or shale were under water, sometimes the weight of the water pressed them so hard that they actually changed the way their molecules locked together and became a different kind of rock. Metamorphosis means changes form, and that's why we call these metamorphic rocks.