â¢ One plate is pushed beneath the other, or equivalent description. â¢ A trench may be formed at the subduction zone. (ii) Explain how subduction leads to volcanic activity. (2 points: 1 point for a correct explanation of one plate being pushed down and melted and 1. point for a correct explanation of molten material /magma rising to the surface near the zone)
The symptoms are generally the same; however the duration of the AFib and underlying reasons for the condition help medical practitioners classify the type of AFib problems. The most common symptom: a quivering or fluttering heartbeat Atrial fibrillation (AFib) is the most common type of irregular heartbeat. The abnormal firing of electrical impulses causes the atria (the top chambers in the heart) to quiver (or fibrillate). View an animation of atrial fibrillation.
1 Atrial fibrillation (AFib) is an irregular heartbeat (arrhythmia) often, but not always, resulting in a fast heart beat (greater than 100 bpm) at rest. 2  Causes of AFib are numerous; for example: 3  overactive thyroid, 4  alcohol use, 5  Pulmonary embolism (a blood clot in the lungs)  Pneumonia,