P Wave ______________sec. What does the P Wave represent? This represents the electrical activity associated with the contraction of the atria. PR Interval ______________sec. What does the PR Interval represent? This is the time from the start of the P wave to the start of the QRS complex. PR Segment ______________sec. What does the PR Segment represent? _____________________________________________________ QRS Interval ______________sec. What does the QRS Interval represent? _____________________________________________________ ST Segment ______________sec. What does the ST Segment represent? _____________________________________________________ T Wave ______________sec. What does the T Wave represent? This represents the electrical activity associated with the relaxation of the ventricles. R-R Interval ______________sec. What does the R-R interval represent? _____________________________________________________ P-P Interval ______________sec. What does the P-P Interval represent? _____________________________________________________ Calculate Your Heart Rate Using the EKG Tracing: _______________________________ bpm. Which waves are positively deflected? Which waves are negatively deflected