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.
This is a particularly interesting area to study because we can observe two types of plate boundaries (divergent and convergent) and their processes in very close proximity. A divergent boundary occurs when two tectonic plates move away from each other.here are three kinds of plate tectonic boundaries: divergent, convergent, and transform plate boundaries. This image shows the three main types of plate boundaries: divergent, convergent, and transform.