English: Spatial arrangement and morphological features of carbonates formed by Ca. Synechococcus calcipolaris G9 grown in BG-11 for one week. (a) HAADF-STEM image of seven cells showing that three cells contain Ca-carbonate inclusions at the cell poles and also at the middle of the cells (red-line arrows). The red-line arrows indicate that carbonate inclusions at mid-cells are generally smaller than those at the cell poles. Cell-1 indicates one cell which contains carbonate inclusions with similar size at the two poles, while Cell-2 seems to have differently sized polar inclusions; (b) EDXS element map of a small area indicated by the red-dashed square on the image (a) showing the spatial arrangement of carbonate (red colors) and polyphosphate (green colors) inclusions; (c) Particle size distributions of carbonates at the cell poles (histogram in black) and at mid-cells (histogram in red).