|
Specimen
087
Gyrosigma are pennate diatoms. Its cells are sigmoid in outline, broad in the central region and narrow towards the apices. Two plates like chloroplasts on either side of the longitudinal axis or are present lying either side of the girdle. it rounded poles and scattered pyrenoids (sub-cellular micro-compartments). The raphe and axial area are uncommonly curved in Gyrosigma and the raphe is S-shaped. They exhibit characteristic gliding movement, caused by streaming cytoplasm by circulation within the raphe, and by the extrusion of mucilage. |