Primary defect in structure is known as :

A malformation is a congenital anomaly due to an intrinsic defect in development which gives a primary defect in structure. A deformation is an abnormal development of an organ due to an extrinsic process. A disruption occurs when a normally developing organ is secondarily damaged by another process. For example, in amniotic band syndrome, a fragment of the amniotic membrane wraps around a poion of the body and damages or amputates it. A sequence is a collection of several anomalies, all of which are due to one malformation, disruption, or deformation.