What is the main function of thrombocytes?

Hint: This is a type of blood corpuscle. Blood is made up of two components plasma and blood corpuscles. Blood corpuscles are also known as formed elements of three types- Red blood cells, White blood cells, and thrombocytes.

Complete answer:
Thrombocytes also known as platelets are colorless non-nucleated cell fragments produced from megakaryocytes, which are special cells in the bone marrow.
They are of different shapes with a size of 2-3 um ( micrometer).
Blood contains 1,50,000- 3,50,000 platelets $mm^{-3}$
Platelets release a number of substances which are responsible for blood coagulation or blood clotting.
The life span of platelets is 7-10 days.
Reduction in their number can lead to serious problems as it leads to clotting disorders. It can lead to excessive loss of blood from the body during injury.
Platelet numbers decrease in severe bacterial infections.

Note:
During an injury, platelets rupture and release thromboplastin. In the presence of calcium ions these thromboplastin acts on prothrombin, an inactive protein and changes it into thrombin, an active proteolytic enzyme. Prothrombin is produced in the liver. During production of prothrombin, vitamin K is essential.
Thrombin then acts on fibrinogen in the presence of calcium ions and changes it into fibrin which undergoes rapid polymerization to form long fibers. These fibres entrap blood corpuscles at the site of injury and form a jelly-like mass called a blood clot.
The whole process of blood clotting occurs in 2 to 3 minutes.