L13 - Coagulation & clotting cascade

Question 1

Where are factors released from when there is a cut/laceration?

Answer 1

• Tissue – activating factors
• Platelets – activating factors
• Plasma – clotting factors

Question 2

How many clotting factors are there?

Answer 2

13 factors

Main ones to remember:
- Factor I ==> Fibrinogen
- Factor II ==> Prothrombin

• All are plasma proteins
• Most produced in liver

Question 3

What are platelets?

Answer 3

• AKA thromocytes
• Function: clotting of damaged vasculature
• How? - stick to tissues (not clotting)
• Thrombopoietin - regulates platelet production
• Lifespan - 7-10 days

Question 4

What is haemostasis?

Answer 4

• The stopping of a flow of blood after damage

4 different ways haemostasis occurs:

1. Vasospasm => narrowing of the arteries caused by a persistent contraction of the blood vessels — vasoconstriction.
   - This narrowing can reduce blood flow.
2. Platelet plug formation (plugging the hole)
3. Coagulation (blood clotting-complex mechanism
4. Fibrin clot formation