atrial fibrillation. n. Abbr. AF. Fibrillation in which the normal rhythmical contractions of the cardiac atria are replaced by rapid irregular twitchings of the muscular wall that cause the ventricles to respond irregularly. Also called a-fib, auricular fibrillation.
continental=on land. here is a good example of plate tectonics, i just had to explain all that stuff. Subduction is when converging plates come together. they make a trench by one plate sliding under the other and into the mantle.
Tectonic shift is the movement of the plates that make up Earthâs crust. The Earth is made up of roughly a dozen major plates and several minor plates. The Earth is in a constant state of change.Earthâs crust, called the lithosphere, consists of 15 to 20 moving tectonic plates.The plates can be thought of like pieces of a cracked shell that rest on the hot, molten rock of Earthâs mantle and fit snugly against one another.he Earth is in a constant state of change. Earthâs crust, called the lithosphere, consists of 15 to 20 moving tectonic plates. The plates can be thought of like pieces of a cracked shell that rest on the hot, molten rock of Earthâs mantle and fit snugly against one another.