Filament arrays within meiotic prophase I mitochondria (ndt80Δ, 8 h in SPM). Left: example cryo-tomogram of a FIB-milled cell with filament arrays (orange arrows) inside mitochondria. Middle: enlarged views (different y-axis rotation compared with the overview) of one filamentous array together with the corresponding side view. Shown are projections of 9.14 nm and 18.28 nm (enlarged views) thick slices. Right: segmentation model highlighting mitochondrial membranes (blue) and filaments in (orange and yellow). Note the regular arrangement of single filaments within the assembly. M, mitochondrion; C, cytoplasm; PM, plasma membrane. Scale bars, 100 nm.