Atherosclerosis and blood clots

Question 1

how does atherosclerosis form

Answer 1

1. damage to the endothelium caused by high blood pressure
2. cause an inflammatory response
3. white blood cells move into the artery wall
4. these white blood cells accumulate cholesterol causing swelling
5. this is called an atheroma
6. calcium salts and fibrous tissues build up forming a plaque
7. this is now atherosclerosis which narrows the lumen of the artery and makes the artery wall less elastic

Question 2

formation of a blood clot

Answer 2

1. platelets come into contact with collagen in artery wall
2. platelets change shape and stick to damaged area forming a platelet plug
3. platelets and damaged tissue release thromboplastin
4. in the presence of calcium ions and vitamin K thromboplastin catalyses the conversion of prothrombin into the enzyme thrombin
5. thrombin catalyses the conversion of fibrinogen into fibrin
6. fibrin is insoluble in water and forms a mesh over the damaged area
7. this mesh traps blood cells forming a blood clot