1.10 - 1.20 health (not definitions) unit 1

what causes atherosclerosis

endothelia become damaged which leads to an inflammatory response and possible blood clotting, substance in the blood build up and harden into a plaque that narrows the artery and raises blood pressure

why does blood need to clot

• prevents blood loss

• prevents entry of harmful bacteria

• provides a framework for repair

explain the process of blood clotting

• platelets release thromboplastin in response to damage

• causes prothrombin to change to its active form , thrombin

• turns soluble fibrinogen into soluble fibrin, forming a mesh that traps blood cells

how do blood clots increase the risk of cardiovascular disease

can detach from the endothelium and enter the circulation, they can become lodged in blood vessels in organs such as the heart or lungs and create a blockage, the blockage restrict blood flow the organs and can cause tissue death which can result in a heart attack

how can CVD lead to a heart attack

• obstruction of a coronary artery (supplies heart muscle) due to an atheroma or blood clot

• results in loss of blood supply to an area of heart muscle

• this causes death of the cells and leads to a heart attack

give factors that increase the risk of cardiovascular disease

• genetics (predispositions)

• age (older people more at risk)

• gender (men more at risk)

• diet

• high blood pressure

• high cholesterol levels

• smoking

• physical inactivity

• obesity

how do dietary antioxidants affect a person’s risk of developing cardiovascular disease

able to stabilise harmful free radicals (molecules with unpaired electrons) they prevent the free radicals from damaging molecules like proteins and DNA which can lead to diseases like CVD and cancer , a greater amount of dietary antioxidants decreases the risk of these diseases

what is the difference between correlation and causation

correlation indicates that there is a relationship between the pattern of two variables

causation indicates that the pattern of one variable is a direct consequence of another variable

what is validity a measurement of

how well the data measures what it is supposed to measure

what is reliability a measurement of

the ability to consistently produce a given result

in studies to determine health risk factors, why is a large sample size important

ensures that measurements taken are more representative of the real world and the population which the sample is taken from, this increases the reliability of the measurements

how does public perception of risk differ from actual risk

• people overestimate risk if something is not under their control, is unfamiliar, or has particularly severe consequences

• people underestimate risk if something only has as effect in the long term

what is meant by a low density lipoprotein (LDL)

• combination of triglycerides from saturated fats and protein

• blocks receptor sites, reducing cholesterol absorption

• known as ‘bad’ cholesterol

how do LDLs contribute to the risk of cardiovascular disease

the high blood cholesterol level caused by LDLs leads to formation of atherosclerosis plaques

what is meant by a high density lipoprotein (HDL)

• smaller types of lipoprotein that contain a significantly larger ratio of protein to lipid

• excretion of excess cholesterol as a part of bile acids

• known as ‘good cholesterol’

why isnt BMI always an accurate measure of obesity

fat and muscle tissue cannot be distinguished so athletes may be incorrectly categorised as obese

what changes to diet and lifestyle can be made to reduce the risk of CVD

• regular exercise

• reduce intake of saturated fat

• maintenance of a healthy weight

• diet low in salt

• reduce stress

• stop smoking and drinking alcohol

how effective are changes to lifestyle and diet in treating CVD

although not themselves effective in the treatment of CVD, they can enhance the efficiency of other methods of treatment

which medicines are used to treat CVD

• statins

• anticoagulants

• antihypertensives

• platelet inhibitors

outline the benefits vs the risks of using statins to treat CVD

lower the level of cholesterol in the blood

however, the can causes liver damage, kidney failure or problems with memory

outline the benefits vs the risks of using anticoagulants to treat CVD

reduce blood clotting , lowering the risk of a heart attack or stroke

however, they can causes excessive bleeding

outline the benefits vs the risks of using antihypertensives to treat CVD

lower blood pressure , reducing damage to artery walls and the build up of atheromas

however, the side effects are headaches, dizziness or fainting

outline the benefits vs the risks of using platelet inhibitors to treat CVD

prevent the formation of blood clots by inhibiting the platelet activating cascade, this prevents thrombosis which can causes a heart attack

they can come with an increased risk of excessive bleeding and also may have some unpleasant side effects such as nausea