1.1 Identify the question and/or problem
Cardiovascular Disease or CVD is the disease of the heart and circulatory system. The two main forms of CVD are Coronary Heart Disease (CHD) and stroke. CVD causes more than a quarter of all deaths in the UK, calculating to more than 161,000 deaths each year.
Coronary Heart Disease (CHD) is the biggest disease people in the UK die from. 1 in 6 men and 1 in 10 women die from CHD. It is responsible for almost 74,000 deaths in the UK, averaging to 200 people each day. More than 25,000 people under the age of 75 die from CHD each year in the UK.
Coronary Heart Disease is when the arteries that supply oxygenated blood to the heart (the coronary ...view middle of the document...
Blood clots form when the blood vessel wall is damaged or blood flows too slowly. Platelets come into contact with the damaged wall and turn from flattened discs to spheres with long, thin projections. The cell surfaces of the platelets change causing them to stick to the exposed collagen and to each other to form a platelet plug. They also release substances which activates more platelets to go through the same changes. The direct contact of collagen with the blood results in a cascade of chemical reactions causing soluble plasma protein called prothrombin to be converted into thrombin. Thrombin is an enzyme which catalyses the reaction converting soluble fibrinogen (another plasma protein) into insoluble strands of fibrin. These fibrin strands form a tangled mesh that traps blood cells to form a blood clot.
1.1b Why is this a problem exactly?
High levels of LDLs (Low Density Lipoproteins) lead to high levels of cholesterol which in a damaged artery can lead to solid plaques being formed causing the artery to become narrower. This leads to high blood pressure and will eventually cause a heart attack. Coronary heart disease is the UK’s biggest killer and therefore there is plenty of pressure on biologists and scientists in general to do something about this distressing fact.
1.2a Methods used to try and solve the problem
According to Dr. Jerry Gordon’s article on ‘How Stuff Works’, cholesterol is a waxy compound of which if you had a handful of would feel like a melted candle. Cholesterol belongs to a group of molecules known as ‘steroids’. Cholesterol is essential for the following:
• Formation of sex hormones
• Production of bile salts to help with digestion
• Conversion into vitamin D when skin is exposed to sunlight
• Formation and maintenance of cell membranes
Doctors and scientists have come up with various possible solutions to reducing the risk of CHD. One of them being the use of statins to lower blood cholesterol. There are two types of cholesterol: High-Density Lipoproteins and Low-Density Lipoproteins (HDLs and LDLs). Essentially, High-Density Lipoproteins are good for you and are considered to be the ‘good’ cholesterol whereas Low-Density Lipoproteins are considered ‘bad’ cholesterol. The higher the amount of LDLs in the body the more likely it is to get Coronary Heart Disease. According to the British Heart Foundation, statins are the most prescribed medicine in the UK. Statins work to reduce the blood cholesterol levels in the body and they are simply a group of medicines aimed to do so. Statins work by inhibiting the enzyme, HMG-CoA reductase which is involved in the making of cholesterol in the liver. Statins are good at reducing LDL levels but they aren’t so efficient at reducing triglycerides.
1.2b Appropriate data of how biologists have used statins
According to Dr Tom Smith’s book Coping with Kidney Disease he explains a study that took place in the 1990s called ‘The Long-term Intervention with Pravastatin in...