blood pressure - ambition, respect, care and...

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Blood Pressure


Heart rate is the rate at which your heart beats. It can be

measured by taking a pulse. A pulse is caused by the

push of the blood through the arteries under the skin.

Heart rate

Pulse, or heart rate, is measured

in beats per minute (bpm).

This can be found by putting your

fingers over an artery and counting

the number of pushes in a minute.

Machines like pulse

oximeters can also be

used to monitor and

measure the pulse rate.


A resting heart rate


The heart is a pump and pushes blood all around your body.

The blood leaves the heart through blood vessels

called arteries.

Blood in the arteries

Arteries have thick

elastic walls

because the blood

in them is under

high pressure.

High pressure is

needed so that the

blood reaches all the

parts of the body.

arteries


Blood pressure is a measure of the pressure exerted

by the blood against the walls of the artery.

What is blood pressure?

Blood pressure is measured

as two numbers, e.g.

The numbers show

pressure readings in

mm of mercury (mmHg).

What do these

numbers mean?

120/80


The big number (‘120’) is the

systolic pressure. This is the blood

pressure during the push of a heartbeat.

“Blood pressure one-twenty

over eighty.”

Systolic and diastolic

The small number (‘80’) is the

diastolic pressure. This is the blood

pressure in-between heartbeats.

120/80


Pressure during a heartbeat


Blood pressure


Collecting data

When researching a topic, like blood pressure, there are

many different ways of gathering data (information).

Sources of data are either:

You need to be careful when using secondary data.

Only take data from sources you trust, such as a text book

or websites belonging to large trustworthy organisations.

Secondary sources –

using data that someone

else has collected.

Primary sources – collecting

data yourself by making

measurements, conducting a

survey or doing an experiment.


Primary or secondary?


How does blood pressure affect health?

Low blood pressure can

cause dizziness, fainting

and poor circulation.

High blood pressure can make blood vessels more likely

to burst, and can cause strokes, brain damage and kidney

damage. It significantly increases the risk of heart disease.

80–100

90–110

110–125

130–150

10

15

20

40

Age Systolic Diastolic

60

60

70

80

The older you get,

the higher your

blood pressure

naturally becomes.

Kevin is 38 years old and his blood pressure is 180/90.

How would you describe his blood pressure?


What affects blood pressure?

poor fitness

increasing age

being overweight high alcohol intake

stress

There are many factors that can increase a person’s

blood pressure, including:

smoking

What advice would you give to

someone who has been diagnosed

with high blood pressure?

diet high in saturated fats.


Cholesterol levels depend on diet and genes, but high levels

of LDL have been linked to eating lots of saturated fats and

few mono/polyunsaturated fats.

What is cholesterol?

Cholesterol is a lipid found in cell membranes and is used

in the production of hormones and bile.

high-density lipoprotein (HDL):

often called ‘good cholesterol’

low-density lipoprotein (LDL):

often called ‘bad cholesterol’.

Cholesterol is transported in the blood by

molecules called lipoproteins, of which

there are two types:


Cholesterol and heart attacks


How does smoking affect blood pressure?

Red blood cells contain a chemical called haemoglobin.

This chemical bonds to oxygen and carries it around in the

blood, ensuring that all the cells get enough oxygen.

When people smoke they breathe in chemicals, including:

nicotine

which increases heart rate

carbon monoxide

which binds with haemoglobin,

preventing it from carrying oxygen.

As the blood carries less oxygen,

the heart has to beat faster to

keep cells supplied.

These effects increase your blood pressure.


How does salt affect blood pressure?

Table salt, or sodium chloride (NaCl), contains sodium ions.

An adult is recommended to have no

more than 6g of salt per day, but

most people eat about 9g.

Eating a diet high in salt can cause an

increase in the volume of water in the

blood. This causes blood pressure to

increase and artery walls to thicken.

These are important for regulating the amount of water in the

body, the movement of muscles, maintaining the pH of blood

and transmitting signals in nerves.


Factors affecting blood pressure


Glossary


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blood pressure - ambition, respect, care and...

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