<prompt> In thromboasthenia there is a defect inPlatelet aggregationPlatelet adhesionDecreased ADP releaseDesordered platelet secretion  <response>: Platelet adhesionPlatelet adhesion referes to the binding of platelets to subendothelial matrix.Platelet membrane glycoprotein Ib-IX is essential for platelet adhesion to subendothelial matrix.Platelet aggregationPlatelet aggregation referres to adherence of platelets to one another.Platelet membrane glycoprotein ddb-IIIa helps in aggregation.Congenital dysfunction of platelet1. Bernard-soulier syndromeDefect in platelet adhesion due to inherited deficiency of glycoprotein Ib-IX.2. Glanzmanns thrombastheniaDefect in platelet aggregation due to inherited deficiency of glycoprotein Ilb-IIIa. 