1.1 - Atherosclerosis/blood clotting Flashcards
1
Q
7 components involved in blood clotting
+ breif defenition
A
- Platelets - cell fragments
- Collagen - protein
- Thromboplastin
- Prothrombin - protein
- Thrombin - enzyme
- Insolube firbin - globular protein
- Soluble fibrin - fibrous protein
2
Q
Desribe the process of Blood clotting
A
- Platelets change shape when in contact with damaged wall- form thin projections and “plug” exposed collagen (temporary)
- Direct contact of blood with collagen also triggers cascade
- Platelets cause release of Thromboplastin (enzyme).
- Thromboplastin catylsyses conversion of prothrombin (protein) - Thrombin (enzyme)
- Thrombin causes conversion of soluble fibrinogen (protein) to insolube fibirin. (enzyme)
- Insolube fibrin fibres cover affected area, trapping more red blood cells and plateles providing a barrier (clot).
3
Q
Define Atherosclerosis
What can it lead to and how? / state 2 potential causes
A
- Atherosclerosis - build up of fatty deposits in vessels which can either block directly or increase chance of being blocked by blood clot (thrombosis)
- Blocking of coronary arteries leads to heart attack
- Blocking of arteries to brain results in stroke.
- High blood pressure or cholesterol etc
4
Q
Describe the process of Atherosclerosis
A
- Damage to endothelium caused by high blood pressure (and more)
- Damage triggers inflamatory response - white blood cells leave vessel and travel to walls. The cells accuulate chemicals from blood - particularly cholesterol - fatty deposit called atheroma builds up.
- Calcium slats + fibrous tissue also builds up at atheroma site, resulting in hard swelling “plaque.
- Plaque can block artery - narrows lumen causing higher blood pressure.
- Positive feedback loop begins.
5
Q
Name for the formation of a blood clot inside an artery
A
Thrombosis
6
Q
Purpose of blood clotting
A
To limit blood loss from damaged vessel and prevent entry of pathogens through wounds;
7
Q
A
