What is the difference between aggregation and coagulation?

Question

When it refers to blood, in particular.

Answer 1

Aggregation, in cardiovascular physiology, refers to the accumulation of platelets to the site of a wound to form a platelet plug or a thrombus.

The coagulation of blood is a complex process during which blood forms solid clots.

Answer 2

Platelet aggregation is a natural process that is initiated within the cascade that control clotting. So it may seem counter to your thinking, but these two terms are mutually inclusive. The steps in coagulation are activation, adhesion and aggregation. During this step, fibrinogen is converted to fibrin which forms a glue between other platelets bearing the receptor GpIIb/IIIa. Imagine it as your arms are GpIIb/IIIa receptors and your legs are bound to a matrix (vWF bound to GpIIa). You hold on to other people and that represents an aggregation of people. That is in essence what happens.

Answer 3

ag·gre·ga·tion (gr-gshn)
n.
A massing together or clustering of independent but similar units, such as particles, parts, or bodies.

Definition of Coagulation

Coagulation: In medicine, the clotting of blood. The process by which the blood clots to form solid masses, or clots.

More than 30 types of cells and substances in blood affect clotting. The process is initiated by blood platelets. Platelets produce a substance that combines with calcium ions in the blood to form thromboplastin, which in turn converts the protein prothrombin into thrombin in a complex series of reactions. Thrombin, a proteolytic enzyme, converts fibrinogen, a protein substance, into fibrin, an insoluble protein that forms an intricate network of minute threadlike structures called fibrils and causes the blood plasma to gel. The blood cells and plasma are enmeshed in the network of fibrils to form the clot.

Tissue can also be subjected to coagulation by various means, as by electrocoagulation, laser coagulation, or photocoagulation.