A normal PR interval measures 0.12-0.20 seconds which is 3 to 5 small boxes on the EKG strip. When you measure a PR interval, you start measuring at the BEGINNING of the p-wave until the BEGINNING of the QRS complex. Here are some simple steps on how to measure the PR interval: Find the P-wave on the EKG strip. Determine where the PR interval is, and to do this you start measuring at the beginning of the p-wave until the beginning of the QRS complex. Count the SMALL boxes between there measurements. Remember each box represents 0.04 seconds.
The role of the excretory system is to rid the body of toxic waste products. Which of these body systems also plays a direct role in removing waste products from the body? A) endocrine B) nervous C) respiratory D) skeletal.
Disposal of liquid waste from human body is done by the excretory system. The system consisting of two kidneys, two ureters, one urinary bladder, and one urethra performs the work of collecting, storing and removing all the liquid waste products from the body.