L14 - Haemostasis & WBC

Question 1

what is the role of platelets in haemostasis?

Answer 1

formation of blood clots at site of bleeding

Question 2

what is von Willebrand factor?

Answer 2

protein used in platelet adhesion - helps blood clotting

Question 3

what is collagen?

Answer 3

component of blood vessels, requires vitamin C for production

Question 4

what is the platelet release reaction?

Answer 4

damage to endothelium allows platelets to bind to exposed collagen, von Willebrand factor increases bond by binding to both collagen and platelets
platelets stick to collagen and release ADP, serotonin and thromboxane A2

Question 5

what is the extrinsic pathway in formation of fibrin?

Answer 5

activator (tissue thromboplastin) acts on 7
7 is activated
forms 7 complex

Question 6

what is the intrinsic pathway in formation of fibrin?

Answer 6

activators (collagen, glass, and others) acts on 12
12 activated
which activates 11
which activates 9
forms 8 complex

Question 7

what is the common pathway in the formation of fibrin?

Answer 7

7 and 8 combine on 10
10 activated
with 5 complex turns prothrombin into thrombin
which turns into fibrinogen into fibrin

Question 8

what is fibrinolysis and how is it initiated?

Answer 8

the enzymatic breakdown of the fibrin in blood clots
initiated by tissue plasminogen activator

Question 9

what are the types of white blood cells?

Answer 9

neutrophil
eosinophil
basophil
monocyte
lymphocyte

Question 10

what are the functions of monocytes and lymphocytes?

Answer 10

immune response, phagocytic and secretory functions

Question 11

what are the key components of the lymphatic system?

Answer 11

• a network of vessels containing the circulating fluid lymph
• composed of lymphocytes and a series of supporting organs e.g. lymph nodes, spleen, thymus

Question 12

what are the key functions of the lymphatic system?

Answer 12

drains interstitial fluid and carries out immune responses