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Blood Pressure

We’ve learned what the cardiovascular system is for…

We’ve learned how the cardiovascular system is structured…

We’ve learned how it responds to changes in our environment…

Now we’ll learn about its biggest health threat and how to keep it healthy.

You know from the heart dissection that arteries, veins and capillaries are the tubes through which our blood flows. When blood flows through your tubes it exerts a pressure on the walls of those tubes. And we have devices called sphygmomanometers to measure that blood pressure. Sphygmos in Greek means pulse, and a manometer is a pressure measurer.

Here’s a side view of your upper arm:

Draw and explain what happens when the blood pressure cuff is tightened.

Draw and explain what happens in your arm at the moment the sphygmomanometer takes its first reading. This is called the systolic reading.

What does this systolic pressure correspond to in the heart?

Draw and explain what happens in your arm at the moment the sphygmomanometer takes its second reading. This is called the diastolic reading.

What does the diastolic pressure correspond to in the heart?

To learn a bit more about blood pressure, we’ll do a mini-experiment. Normally, your blood pressure is measured in your left arm while you are at rest and are relaxed. Think of a variable you could immediately and safely test to see its effect on your blood pressure.

Person / Resting
Blood Pressure / Variable added / Hypothesis – and why do you think that? / New
Blood Pressure

As we discuss these results, is there anything of note to conclude?

Hypertension, or high blood pressure, is a major health issue in America, and it has many causes. As you read the article entitled “Blowing a Gasket” from the December 6, 2004 issue of TIME magazine, list the Causes and Effects of Hypertension as you discover them in the article.

CausesHYPERTENSIONEffects

After you create your lists, develop a mnemonic device (mnemos means “memory” in Greek) to help you remember the causes and effects of hypertension. “PEMDAS” is an example of a mnemonic device you may have used in math class to remember the order of steps in simplifying expressions; “Every Good Boy Does Fine” is a mnemonic for remembering the lines of a treble clef in music.

Which of the causes can people control?

Can these causes be controlled in all cases, or does it depend upon a person’s circumstances? We’ll discuss!