1. Preventing Blood Loss
1.1.3.a,b,c,d

2. Learning Objectives
describe the first-aid procedure to prevent excessive blood loss;
outline the mechanism of blood clotting as an enzyme controlled process, with reference to the role of platelets, damaged tissue, thromboplastin, calcium ions, prothrombin, thrombin, fibrinogen and fibrin;
state that enzymes are globular proteins;
explain how the structure of a globular protein enables enzyme molecules to catalyse specific metabolic reactions, with reference to the specificity of the active site, the formation of enzyme substrate complexes and the lowering of activation energy;

3. http://www. youtube. com/watch

4. Boardworks AS Biology Circulation and Blood
Blood clotting
Teacher notes
Serum is plasma from which fibrinogen has been removed, therefore preventing it from clotting. Serum is used to treat plasma loss in people with severe burns (loss of outer layer of skin means tissue fluid, but not blood cells, are rapidly lost).

5. Substances in blood clotting
Boardworks AS Biology
Circulation and Blood
Substances in blood clotting

6. Activation energy

7. Mechanism of Enzyme action