Describe the sequence of events during a blood clot.

Hemostasis includes three steps that occur in a rapid sequence:

Explanation: 1) vascular spasm, or vasoconstriction, a brief and intense contraction of blood vessels; (2) formation of a platelet plug; and (3) blood clotting or coagulation, which reinforces the platelet plug with fibrin mesh that acts as a glue to hold the clot.

or:

The Blood Clotting Process

Injury. A small tear in a blood vessel wall (for example, from a cut on the skin or an internal injury) causes bleeding.

Vessel constriction. To control blood loss the blood vessel narrows (called constriction), thus limiting blood flow through the vessel.

Platelet plug. ...

Fibrin clot.