National 4 ScienceHuman HealthBlood Pressure

Learning Intentions: What is blood pressure? How can blood pressure be measured? What can affect blood pressure? What are the effects of high blood pressure? What effects do low blood pressure have on

the body?

Blood Pressure

When the heart beats it pushes blood into the arteries at high pressure.

This pressure is called blood pressure

What is blood pressure?

How can blood pressure be measured?

• The low tech method of measuring blood pressure is:• Stethoscope and

mercury manometer

• The high tech method of measuring blood pressure is:• Digital

sphygmomanometer

When measuring blood pressure there are two numbers

E.g. Average blood pressure is 120/80mmHg

The high number is caused when the heart contracts pushing blood into the arteries

The low number is when the heart relaxes allowing the chambers of the heart to refill

Measuring blood pressure

Position Blood pressure (mmHg)

Sitting quietly

After exercise

Measure your blood pressure

Answer the following questions:1. What effect did exercise have on your blood pressure?

2. If we wanted to make the test more reliable what would we have to do?

There are 6 things that can affect blood pressure

What are they? Being overweight Not taking enough exercise Eating a diet high in fat Eating a diet high in salt Drinking alcohol to excess Having a stressful lifestyle

What has an effect on your blood pressure?

High blood pressure can lead to: Heart attack – damage to heart muscle caused

by a blockage to blood vessel supplying oxygen to the heart

Angina – intense cramp like pain in the chest indicating heart not getting enough oxygen. Goes away with rest

Stroke – blockage of a blood vessel in the brain, may result in brain damage

What effect does high blood pressure have on your body?

Low blood pressure can result in fainting and may indicate heart failure

What effect does low blood pressure have on the body?

1. What is blood pressure?2. How can blood pressure be measured?3. What can affect blood pressure?4. What are the effects of high blood pressure?5. What effects do low blood pressure have on the body?

Quiz