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Blood Pressure

The force of blood exerted on the inside walls of blood vessels. Blood pressure is expressed as two numbers. For example, a blood pressure result of 120/80 is said as "120 over 80."

PubMed Health Glossary
(Source: NIH - National Institute of Diabetes and Digestive and Kidney Diseases)

About Measuring Blood Pressure

The heart is responsible for supplying the organs and tissues of the body with blood. To do this it pumps blood into the large vessels of the circulatory system with every beat. The blood that is pumped into these vessels puts pressure on the walls of the vessels. When the heart muscle contracts during each heartbeat, the pressure rises as well. When measuring blood pressure, there are two different values:

Blood pressure is measured in units of "millimeters of mercury"; written mm Hg for short. Blood pressure measurements are always given in pairs, with the upper (systolic) value first, followed by the lower (diastolic) value. So someone who has a reading of 132/88 mm Hg (often... Read more about the Blood Pressure

Terms to know

Blood
A tissue with red blood cells, white blood cells, platelets, and other substances suspended in fluid called plasma. Blood takes oxygen and nutrients to the tissues, and carries away wastes.
Blood Vessels
Tubes that carry blood to and from all parts of the body. The three main types of blood vessels are arteries, capillaries, and veins.
Diastolic Pressure
The blood pressure when the heart rests.
Systolic Pressure
The blood pressure when the heart pushes blood out into the arteries.

Related conditions

Terms to know

Blood
A tissue with red blood cells, white blood cells, platelets, and other substances suspended in fluid called p...
Blood Vessels
Tubes that carry blood to and from all parts of the body. The three main types of blood vessels are arteries...
Diastolic Pressure
The blood pressure when the heart rests....
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