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.
Uplift and erosion help bring metamorphic rock to the Earth's surface. Examples of metamorphic rocks include anthracite, quartzite, marble, slate, granulite, gneiss and schist. Anthracite is a type of coal with a high carbon count, few impurities and with a high luster (meaning it looks shiny).Marble is a metamorphic rock that is formed from the sedimentary rock limestone.etamorphic Rock Facts. Enjoy our metamorphic rock facts for kids. Find interesting information and a range of examples that help explain what metamorphic rocks are and what makes them different from other kinds of rocks. Metamorphic rocks have been changed over time by extreme pressure and heat.