1. what happens when platelets come into contact with damaged vessel wall?
- they change from discs to spheres with long projections and their cell surfaces change making them stick to the exposed collagen and to each other forming a platelet plug. they also release substances to activate more platelets.
- they release a sticky substance and stick to the formed plaque, forming a platelet plug. they also release substances to activate more platelets
- they release a chemical which activates more platelets causing a build up of platelets and so blood cannot flow though properly.
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Other questions in this quiz
2. what causes the pain of angina? (usually experienced during exertion)
- the heart lacking oxygen causes it to respire anaerobically, this results in chemical changes triggering the pain.
- a build up of fat deposits causes a blood clot which narrows the arteries and stops the right amount of blood circulating around the body
- supply of blood to heart and brain is slightly interupted
3. what happens when there is a plaque in an artery?
- blood flow speeds up and so pressure increase and the artery becomes more damaged
- the artery becomes narrower and positive feedback builds up, causing raised blood pressure.
- the artery narrows and blood flow slows down, decreasing blood pressure
4. water is what type of molecule?
5. during ventricular systole, the pressure of blood against the atrioventricular valves does what?
- damages them
- closes them
- opens them