(also called thrombocytes) are substances found in blood.
They promote coagulation or blood clotting. When a blood vessel
is injured, causing bleeding, platelets in the blood begin
to accumulate at the injury site, adhering to each other and
to the torn vessel lining. This aggregation loosely plugs
the injury, preventing further blood loss until the blood
can clot, forming a scab and stopping the bleeding. Platelets
are often visible as a clear, viscous liquid which forms over
a small cut.
Anticoagulant drugs, such as aspirin, often
work by inhibiting platelet aggregation and blood clotting.
This results in longer bleeding times, but also reduces the
chance that a blood clot will form inside an artery, possibly
leading to stroke.
Article : "VASCULAR
by Catherine E. Myers. Copyright © 2006 Memory Loss and the Brain