title: Ultrastructural observations on changes in cell shape in chromatophores of the sea urchin Centrostephanus longispinus.
abstract: Alterations in cell shape of the light-sensitive chromatophores of the sea urchin Centrostephanus longispinus were studied by scanning- and transmission electron microscopy. Transition of the aggregated to the dispersed state is accompanied by incorporation of vesicles into the membrane of the pigment cell. During disperson a system of microtubules originating from centriole-like structures is established throughout the stellate cell. Within restricted areas of the cell, cytoplasmic differentiation and condensation is found. The possible functional significance of the findings is briefly discussed.
mesh_terms: D000818:Animals; D002462:Cell Membrane / Q000648:ultrastructure; D002467:Cell Nucleus / Q000648:ultrastructure; D002856:Chromatophores / Q000502:physiology / Q000648:ultrastructure*; D003593:Cytoplasm / Q000648:ultrastructure; D003594:Cytoplasmic Granules / Q000648:ultrastructure; D003624:Darkness; D008027:Light; D010860:Pigments, Biological; D011554:Pseudopodia / Q000648:ultrastructure; D012617:Sea Urchins / Q000648:ultrastructure*
chemical_list: D010860:Pigments, Biological