Water rushing through a hose exerts pressure on the hose, and in the same way, blood surging through your blood vessels exerts pressure on the vessels.
It’s important for a doctor to know your blood pressure, because this tells him the strength of your heart, the condition of your arteries, and other important things about your health.
When a doctor takes your blood pressure, he attaches a rubber cuff to your arm, just above the elbow. This cuff is like an empty balloon, and can be filled with air. The doctor pumps up the cuff until it’s so tight that it stops the flow of blood through the artery in your arm. Then he lets the air out of the cuff, and the first rush of blood through the artery is “read” by a tube containing mercury. This mercury tube shows the doctor your blood pressure “reading.”
This first, or maximum, reading tells the doctor your blood pressure when your heart is pumping. The second, or minimum, reading is then taken to show your blood pressure when your heart is in its resting stage. So your blood pressure reading always consists of two numbers, called the ‘maximum/minimum blood pressure.”
The average blood pressure reading of a healthy adult is 120/80. But blood pressure readings can vary in the same person at different times.
Related Posts
-
Do Fish Have Blood and Hearts, What Color Is Fish Blood, and Why Don’t Fish In Stores Have Blood?
Fish do have blood, and it is red. Other cold-blooded animals, like amphibians and reptiles, also have red blood. Fish have a circulatory system with blood and a heart as the pump just…
-
What Do Weathermen Mean by High Pressure and Low Pressure?
The weight of air pushing against the earth is what weathermen call air pressure. This weight changes from place to place and from time to time in the same place. These changes are…
-
How High Is the Blood Pressure of a Giraffe and Do Giraffes Get Heart Attacks and Strokes?
In an adult giraffe, the systolic blood pressure, the pressure when the heart contracts to pump blood through the body, is about 200 millimeters of mercury at the level of the heart, about…
-
Why Does Blood Thicken In Winter and How Does the Human Body Control the Thickness of Blood?
Blood doesn't thicken in winter, even though it may sometimes feel like it. In fact, it might tend to be thicker in summer, when the body loses water through sweating and people need…
-
Why is blood-typing important and how is mixing incompatible blood types dangerous?
Mixing incompatible blood quickly creates a sea of red dumplings swimming in yellowish liquid, bringing on instantaneous death. In 1900 Dr. Karl Landsteiner discovered the A, B, and 0 blood groups and demonstrated…
-
Who Discovered Blood Plasma and How does separating red blood cells and plasma extended the shelf life?
Whole blood can be safely stored for only a few days. That had always meant that blood donations had to come from local sources and be given at the time of need. Blood…
