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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 blood vessel.
2. Platelets stick to damaged wall and to each other, forming a platelet plug.
3. Fibrin mesh traps blood cells, forming a clot.
1.…read more

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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 its lowest in the artery when the ventricles are relaxed.…read more

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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.
3. Diastole Elastic recoil as the heart relaxes causes low pressure in the heart, helping to
refill the chambers with blood from the veins.
At each stage blood moves from a higher to lower pressure.…read more

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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 efficient at delivering substances around the body:
The blood leaves the heart under pressure and flows along arteries and then arterioles
(small arteries) to capillaries.
There are extremely large numbers of capillaries.…read more

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Cardiovascular disease:
Risk factors for CVD:
High blood pressure
Blood cholesterol and other dietary factors
Genetic inheritance
While some of these you can control, while others you can't.…read more

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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 are made of the elements Carbon , Hydrogen and Oxygen , although they have a much
lower proportion of water than other molecules such as Carbohydrates. They are insoluable in
Lipids perform many functions, such as:
o Energy Storage
o Making Biological Membranes
o Insulation
o Protection e.g.…read more

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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 have more than one C=C bond.
If fatty acids are unsaturated, their shape is altered from a saturated molecule so the molecules
in the Lipid push apart, thus making it more fluid and oily.…read more

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Defining `overweight' and `obese':
BMI= mass/kg and
waisttohip ratio
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 major transport lipoproteins:
Lowdensity lipoproteins (LDLs) the main cholesterol carrier in the blood. The
triglycerides from saturated fats in our diet combine with cholesterol and protein to form
LDLs.…read more

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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 figure. A highsalt diet causes kidney
to retain water. Higher fluid levels in the blood result in elevated blood pressure with the
associated CVD risks.…read more


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