1B: Lifestyle And Diseases Flashcards
what is the function of platelets?
to prevent blood loss and to prevent cuts from getting infected via pathogens
what is the body’s mechanism for blood clotting?
thrombosis
what is released when platelets make contact with damaged skin tissue ?
serotonin and thromboplastin
what is the function of serotonin during blood clotting?
causes smooth muscles to contract which narrows the blood vessels - this means less blood loss
what is the function of thromboplastin during blood clotting?
it’s an enzyme which controls the formation of a clot
what does thromboplastin do during the formation of a blood clot?
thromboplastin initiates a cascade system which leads to the formation of a clot?
what is the process of thrombosis ?
• thromboplastin catalyses the conversion of prothrombin to thrombin by using calcium ions
• thrombin acts on fibrinogen which is converted to fibrin
• fibrin forms a mesh of fibres around the damaged tissue
• more platelets and blood pour from the wounds and get trapped in the mesh- this forms the clot
• special proteins in the platelets contract, tightening the clot
what happens in a thrombus loosens?
an embolus forms which travels through the blood - this can block a blood vessel
what happens if a blood vessel is blocked by a embolus?
a heart attack or stroke can occur
what is thrombosis?
the formation of a blood clot inside of a blood vessel
what is atherosclerosis
a disease that can lead to CHD and strokes
what is the problem with fatty deposits
- the deposits can cause an artery to become narrower, increasing the chances of it being completely blocked by a clot (thrombus)
- blood supply to cells can be cut off or limited
cut off blood supply can be lead to a heart attack or stroke
differnce between the causes of a heart attack and the causes of a stroke
heart attack : cut off blood supply to heart
stroke : cut off blood supply to brain
what can a build up of blood in an artery cause
death if the artery bursts open
what is deposition
a process by which substances are added to a surface
what is plaque
an abnormal build up of substances or tissue on a body part or organ
what is endothelium
a single layer of cells lining various organs and cavities in the body
what is cholesterol
a type of lipid made in the liver, found in the blood and in all cells of the body
what is an atheroma
a build up of fatty deposits
how does an atheroma form
-endothelium lining damaged
- inflammatory response occurs as white blood cells move to the artery
- plaque of WBCs, cholesterol, calcium salts and fibres forms (atheroma)
-leads to artery narrowing and stiffening
where is overestimation of risk common
when risks are :
- involuntary
- not natural
- unfamiliar
- dreaded
- unfair
- very small
what are perceptions of risk
what really drives peoples behaviour and actions
what treatments are available for CVD
- ACE inhibitors
- Statins
- Anticoagulants
- platelet inhibitators
what are ACE inhibitors?
How do they work?
(also known as antihypertensives)
used to treat high blood pressure and heart disease
they work by causing the relaxation of blood vessels and a decrease in blood volume - leads to lower blood pressure and lower oxygen demand from the heart
blocks the conversion of Angiotensin I to
Angiotensin II - preventing arterial constriction
advantages of ACE inhibitors
help relax the veins and arteries to lower blood pressure- help control heart failure
disadvantages of ACE inhibitors
increases potassium levels in blood (hyperkalemia)- can damage heart and cause heart attack, fatigue
what are statin?
How do they work?
a group of medicines that can help lower the level of low-density lipoprotein (LDL) cholesterol in the blood. And protect the inside of artery walls
they work by blocking the enzyme which
produces cholesterol in the liver
advantages of statins
lowering cholesterol and protecting against a heart attack and stroke
disadvantages of statins
muscle pain, digestive isseus, liver damage, nausea
what are anticoagulants?
How do they work?
they help reduce blood clotting and reduce chances of blood vessel becoming blocked by a blood clot
they work by thinning the blood -> less blood clotting happens as there is less risk of the artery lining becoming damaged
advantages of anticoagulants
ca be used on people who already have blood clots/ heart disease
also prevents existing clots from growing and prevents new ones forming
disadvantage of anticoagulants
can cause excessive bleeding, fainting, death, swelling of tissues, cannot get rid of blood clots
what are platelet inhibitory drugs ?
How do they work?
They make platelets less sticky therefore help prevent blood clots from forming in the arteries
advantages of platelet inhibitors
can be used to treat people who already have blood clots/CVD
disadvantages of platelet inhibitors
excessive bleeding, liver function problems, diarrhoea, nausea, rashes
