What is Pulse?
[[File:Pulse sites-en.svg|thumb]] A '''pulse''' (or '''heartbeat''') is a throbbing of [[blood vessel]]s as [[blood]] goes through them. You can feel someone's pulse in their [[wrist]], [[thumb]] or [[neck]], where vessels are closer to the [[skin]]. A normal pulse is below 100 beats per minute. Our pulse quickens when we [[Physical exercise|exercise]] because the muscles being used need more [[oxygen]]. Unusually fast or slow or irregular pulse might mean sickness. There are normally four heart sounds. Two of them, S1 and S2, can be heard with a [[stethoscope]]. Two other sounds, S3 and S4, can not be heard, but they can be seen using a machine called a [[phonocardiograph]]. [[Pulse (legume)|Pulses]] is a term for [[pea]]s, [[bean]]s and [[lentil]]s. {{biology-stub}} [[Category:Cardiovascular system]]