First, I want to start by giving you a brief
background about the circulatory system.
Blood and blood vessels are two of the three
parts of the circulatory system - the third being
the heart, which pumps the blood of these blood
vessels by rhythmic contractions. The main blood
vessels are veins, arteries, and capillaries.
Veins carry deoxygenated blood from the body to
the heart to be oxygenated. Arteries carry
oxygenated blood from the heart to the rest of the
body; the aorta is the largest artery in the human
body. Capillaries, the tiniest blood vessels in
the body, function to exchange nutrients and
oxygen for waste products; they connect the
arteries and the veins. The system of blood
vessels is very important to our bodies so that
our cells can be replenished with oxygen and
Blood pressure is the pressure created of the
blood against the walls of the arteries. It is
measured as diastolic and systolic. Diastolic
blood pressure is the pressure between beats when
the heart is at rest, and systolic blood pressure
is the pressure during heart beats. On a blood
pressure monitor, the systolic blood pressure is
read before the diastolic. You might here the
doctor saying that your blood pressure is "110
over 70"; your systolic is 110 mm Hg (millimeters
mercury) and your diastolic is 70 mm Hg. Mercury
is used to measure pressure, and you can find
conversions to Pascals and atmospheres online.
Blood pressure between 90/60 to 120/80 is usually
the healthiest range.
Remember blood pressure (in mm Hg) is different
that heart rate (in beats per minute). The first
measures pressure of blood against walls of
arteries, and the other measures the rate at which
your heart is beating.