Outline the formation, structure and function of the platelet.
The structure of the question outlined exactly what was expected. Platelets are formed in the
bone marrow from budding of megakaryocytes. Granulocyte colony stimulating factor and
thrombopoeiten play a role in the process and they have a life span of about 10 days. It was
expected candidates could describe or draw the structure detailing they have no nucleus, the
presence of mitochondria and granules and provide some detail of the important external
surface proteins (glycoproteins, ABO, human platelet antigens). Better answers also described
the internal microtubule structure and related this to function (allows contraction and shape change). The description of function required detail around the importance of platelet plug
formation and the role of adhesion, aggregation and activation in this process.