title: The fine structure of larvae of Taenia hydatigena aged seven and ten days.
abstract: Studies on the fine structure of larval T. hydatigena during their initial phase of development have shown that the structure of their differentiating tegument is dissimilar to that of the adult cestode. It differs from it both in the number and shape of organelles (microvilli, rod-shaped bodies, invaginations of the basal membrane, mitochondria) present at the early ontogenesis of the bladder. Typical of the initial phase of the production of rod-shaped bodies in sub-tegumental syncytial cells is their limited appearance in the distal cytoplasm and the character of microvilli lacking both an electron-dense layer below the plasma membrane and distal points. At 10 days, during the further differentiation of the perinuclear cytoplasm, the number of rod-shaped bodies and invaginations of the basal membrane in the tegument increases, and more vesicles and cisternae of the Golgi apparatus appear in the cells. The layer of circular muscles and fibrils has not yet started to differentiate in the subtegument. It is dependent for its differentiation on the secretory activity of cells with dilated cisternae of the endoplasmic reticulum. The scolex anlage and the zone of growth of the bladder differentiate from proliferating germ cells. Glycogen-depositing cells are present at this stage of development. Later these cells change into glycogen-containing structures.
mesh_terms: D013621:Taenia / Q000254:growth & development / Q000648:ultrastructure*