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.
P wave-the arch preceding the QRS complex. Q wave-the first negative (downward) deflection of the complex. In some leads, it will not be present. In some cases, the complex begins with an R wave.R wave-the first positive (upward) deflection of the QRS complex.RS-the complex represents the depolarization of the ventricles. This is followed by an isoelectric segment. T wave-this represents ventricular repolarization. Atrial Contraction-the atria mechanically contract starting at the beginning of the P wave, until the beginning of the QRS complex.