EGD or Upper Endoscopy Procedure. The device used during an EGD procedure is called a flexible endoscope. It is tubular in shape and is very similar to the colonoscope that gastroenterologists use to examine a patientâs colon during a colonoscopy procedure, just thinner in diameter.
What causes ocean currents? Ocean currents result from two processes - the action of wind on the surface of the water, and from variation in water temperature that causes movement- a process known as convection. Convection occurs because the oceanic waters heat up becoming less dense.
Wind-driven currents are caused by the return of large circulation cells, of which there are three between the equator and the poles. Find out how circulation cells also move heat over the planet with help from the chair of a department of environmen...tal studies in this video (02:29) on wind-driven currents.