| what is atherosclerosis? | a diseases that hardens the arteries caused by the build up of plaque leading to CVD's |
| processes involved in the development of atherosclerosis | the endothelium is damaged (e.g. by smoking, high cholesterol, high blood pressure)
this sends out an inflammatory response which cause white blood cells to move into the artery
over time, white blood cells, cholesterol, calcium salts and fibres build up forming a plaque
if the plaque is not dealt with it will harden to form an atheroma
the formation of an atheroma can cause increased blood pressure which will lead to the further damage of the endothelium causing another plaque formation |
| what can atherosclerosis lead to? | cardiovascular diseases (CVD) like: stroke, myocardial infraction (heart attack), angina, aneurisms |
| why does atherosclerosis lead to CVD's? | plaque limits the flow of oxygenated blood to cells
cell are unable to respire and they die |
| how is a blood clot formed
(in the arteries) | the process of thrombosis
blood vessels are damaged
platelets attach to the exposed collagen fibres
thromboplastin is released from the platelets triggering the conversion of the prothrombin protein into the thrombin enzyme
calcium ions and vitamin K must be present for the conversion to occur
Thrombin then catalyses the conversion of soluble fibrinogen into insoluble fibrin
fibrin forms the a network of fibres that traps platelets and red blood cells to form the blood clot |
| why do blood clots lead to CVD's? | red blood cells get trapped in the clot
not enough red blood cells get past to carry oxygen to the cardiac cells
the cardiac cells are unable to respire so they die
this causes a CVD |
| what factors affect the risk of developing a CVD? | genetics
age
diet
gender
smoking
obesity |
| how does genetics increase the risk of CVD? | genetic predisposition to high blood pressure
which increases the risk of damage to the endothelium |
| how does age increase the risk of CVD? | arteries become less elastic with age
this will generate a high blood pressure
increased risk of damaged to the endothelium |
| how does diet increase the risk of CVD? | increased cholesterol, sat fats and salts
increased build up in arteries
arteries become narrower
risk of damage to the endothelium due to higher blood pressure generated |
| how does gender increse the risk of CVD? | men are more likely to develop CVD's because oestrogen in women make arteries more elastic |
| how does high cholesterol levels increase the risk of CVD? | increases the likelihood of the formation of a plaque |
| how does smoking increase the risk of CVD? | nicotine narrows the arteries
this generates a high blood pressure
increases the risk of damage to the endothelium |
| how does obesity increase the risk of CVD? | more fatty deposits
narrows the artery
generates a higher blood pressure
increased risk of damage to the endothelium |
| how does physical inactivity increase the risk of CVD? | can lead to obesity |
| what is the difference between correlation and causation? | variables have a causal relationship in causation - one variable will cause the other variable to happen e.g. high fat diet has a causal relationship with weight gain
variables are independent of each other in causation - one variable does not have a direct effect on the other variable however they could still follow a distinct trend e.g. high fat diet against death from CVD |
| what is risk? | the probability that an event will occur |
| why do people overestimate risks? | not under human control
unnatural
unfamiliar
unfair
dreaded
social media |
| why do people underestimate risks? | long term effect
risk is very small
lack of information |
