Main functions of blood (4)
delivery, waste collection, communication routes (endocrine), defense
Composition of blood
plasma (cell free)- 55%, buffy coat, white bloat cells, platelets (1%), erythrocytes (45%)
Serum definition
Liquid component of blood, no clotting factors (plasma with no clotting factors)
Serum functions (3)
transport, inflammatory response/immunity, oncotic pressure
Albumin and its function (2)
Most abundant plasma protein.
- Regulates oncotic pressure (solubilised and retained in blood stream) + transport (charged, polar, non-specific binding)
Serum protein electrophoresis (SPE) process/ goal
Uses agarose/ polyacrylamide gel electrophoresis and is able to separate proteins based on charge and size. (Used for diagnosis, monitoring disease progression and assessing organ function)
- Limitations: changes missed, some proteins too low to detect
Albumin levels (serum protein)- increases/decreases as disease signals
Alpha-globulins levels (serum protein)
Beta-globulin levels (serum protein)
Gamma-globulins levels (serum protein)
Acute phase proteins levels (serum protein)
How are serum enzymes used in diagnosis?
Haemotosis
formation and dissolution of blood clots
Clotting (and what things are involved)
Forming solid mass of blood to plug vessels. Uses platelets (secretory specialists) and clotting factors.
Thrombosis
Clot attached to blood vessel walls
Embolus
Detached thrombosis that blocks blood flow in diff part of bodyh
Blood clot stages
Thrombin activation (clotting cascade)
Intrinsic, extrinsic and common.
- Can be used for positive feedback
- Proteases have multiple points of regulation
- Coagulation complexes dependent on Vitamin K
Intrinsic clotting cascade
Blood can clot without any other biological agents.
- Initiated with surface contact with collagen
- Cascade of protease cleaving + activating other factors
Extrinsic clotting cascade
Requires factors not found in blood
- tissue damage, protein tissue factor (TF) exposed to blood
Common clotting cascade
X -> Xa -> cleaves prothrombin -> thrombin
Limiting clot formation + degradation/breakdown of clot
- Limiting clot: proteases inhibitors
- Clot breakdown: Plasmin breaks down fibrin mesh