√Atrophy o Decrease in cell size and/or decrease in cell numbers,resulting in decrease in size and weight of a tissue or organ. Distinct from agenesis,aplasia and hypoplasia. Physiological (developmental)vs pathologic atrophy  Atrophy  Decrease in cell size and/or decrease in cell numbers, resulting in decrease in size and weight of a tissue or organ.  Distinct from agenesis, aplasia and hypoplasia.  Physiological (developmental) vs pathologic atrophy