White Blood Cells and Haemostasis Flashcards
What type of cytokines do neutrophils release?
Pyrogens
What do pyrogens do?
Fever causing substance
What are the two main cytokines basophils release?
- Histamine
- Heparin
What does heparin do?
Is a blood thinner
What is lymphoma?
Cancer in the lymphatic system resulting in uncontrolled growth of lymphocytes
What is leukemia?
Cancer of blood forming tissue leading to the production of abnormal white blood cells
How are platelets formed?
Cell fragments produced in the bone marrow from megakaryocytes
What do platelets contain?
- Mitochondria
- Smooth ER
- Vesicles filled with cytokines
What is the role of platelets?
Haemostasis
What is haemostasis?
Clotting of blood
What are the three steps in haemostasis?
- Vasoconstriction
- Formation of platelet plug
- Coagulation
What is vasoconstriction?
The constriction of the vessel decrease blood flow and pressure temporarily
What causes vasoconstriction?
Paracrine molecules from the endothelium
What are the steps for the formation of a platelet plug?
- Exposed collagen binds and activated platelets
- Release of platelet factors
- Factors attract more platelets
- Platelets aggregate into platelet plug
What is coagulation?
The formation of a clot
What are the two pathways of coagulation?
- Intrinsic
- Extrinsic
How does the intrinsic pathway begin?
- Inactive factor 12 comes in contact with collagen and becomes active
- Active factor 12 and Ca activates factor 11
- Active factor 11 and Ca activated factor 9
- Active factor 9 and factor 8 and Ca activates factor 10
How does the extrinsic pathway begin?
- Damage to the cell exposes tissue factor 3
- Tissue factor 3 binds with active factor 7
- This complex activates factor 10
What are the steps of the common pathway?
- Active 10 activates prothrombin to become thrombin
- Thrombin activates fibrinogen to become fibrin and activated factor 13
- Active 13 and Ca activates fibrin to create cross linked fibrin
What is fibrinolysis?
The process of blood clots dissolving
What are common symptoms of having a coagulation disorder?
Bruise easily and may be prone to internal bleeding
How are coagulation disorders usually aquired?
They are often inherited
What is the most common example of a coagulation disorder?
Haemophilia
What is the most common form of haemophilia and what causes it?
Haemophilia A which is caused by deficiency in factor 8
