E. (1) sea shell fossils (2) it is made of old ocean floor that got uplifted during collision. 4. At convergent plate boundaries, the volcanic mountain chains that form are called (1) ________ in an ocean-. ocean setting and (2) __________ in an ocean-continent setting.
Poor R wave progression is a vague term used to describe the transition in voltage in the precordial leads of an electrocardiogram (ECG). It is not a diagnosis but simply describes a pattern frequently noted. In a normal individual there is a progressive increase in the magnitude of the voltage in the leads from V1 to V4.
On this count the P wave is always positive in lead II and always negative in lead aVR during sinus rhythm. Conversely, a P wave that is positive in lead II and negative in lead aVR indicates normal P wave axis and sinus rhythm. The QRS Complex. The second wave is the QRS complex. Typically this complex has a series of 3 deflections that reflect the current associated with right and left ventricular depolarization. By convention the first deflection in the complex, if it is negative, is called a Q wave.