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Unit 1:
Lifestyle, Health and Risk























Active transport:

Some key features of active transport:

It pumps substances against a concentration gradient (from a low to high concentration).
It requires energy from respiration, which it obtains from the molecule ATP.
It needs a protein carrier in the membrane.


















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Atherosclerosis:

1. Damage to endothelium
2. Inflammatory response
3. WBC move into artery wall
4. Cholesterol accumulates= atheroma
5. Calcium salts & fibrous tissue build up= plaque
6. Artery loses elasticity
7. Artery narrower= higher blood pressure
8. Positive feedback



Blood clot:

1. Platelets stick to damaged wall of the…

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Blood pressure:

An elevated blood pressure is called hypertension.
Sphygmomanometer is the traditional device used to measure blood pressure.
Systolic pressure= pressure in the artery is highest when the pace of the cardiac cycle
when the ventricles have contracted and forced blood into the arteries.
Diastolic pressure= pressure is at…

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The cardiac cycle:

The cardiac cycle is continuous and has no start or end. There are 3 stages that are atrial systole,
ventricular systole and diastole.

1. Atrial systole The atria contracts, forcing blood through the ventricles.
2. Ventricular systole Contraction of the ventricles pushes blood up into the arteries.…

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Many animals, including invertebrates have a closed circulatory system in which the blood is
enclosed within tubes. This generates higher blood pressures as the blood is forced along fairly
narrow channels instead of flowing into large cavities. Which means the blood travels faster and
so the blood system is more…

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% change=





Cardiovascular disease:

Risk factors for CVD:

High blood pressure
Obesity
Blood cholesterol and other dietary factors
Smoking
Genetic inheritance

While some of these you can control, while others you can't.



Carbohydrates:

The term carbohydrate mean `hydrated carbon'
They have a general formula of
(Cx
H2

O)n





























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Energy units:

1000 calories is called kilocalories (also called Calories with a capital C)
4.18 joules = 1 calorie
1 kilojoule (1 kJ = 1000 joules)







Lipids:

Lipids are made of the elements Carbon , Hydrogen and Oxygen , although they have a much
lower proportion of water than other…

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Fatty acids may be saturated or unsaturated. A fatty acid is saturated if every possible bond is
made with a Hydrogen atom, such that there exist no C=C bonds. Saturated fatty acids on the
other hand do contain C=C bonds. Obviously monounsaturated fatty acids have one C=C bond,
and polyunsaturated…

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Defining `overweight' and `obese':

BMI= mass/kg and
waisttohip ratio
2

height2/m= body



Consequences of obesity:

Increases your risk of coronary heart disease and stroke
Greatly increases risk of type II diabetes
Obesity can raise your blood pressure and elevate your blood lipids levels, two classic risk
factors for CVD.

Two…

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Salt:

You need some salt in your diet for the healthy functioning of your body but too much can have
adverse effects. The Food Standards Agency recommends a salt intake of no more than 6g of salt
per day for an adult, but the UK average intake is double that…

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