TEM analysis of the effect of NaHS on mesophyll cell (A–D) and bundle sheath (E–H) chloroplast ultrastructure of maize leaves.(A, E), –Fe; (B, F), –Fe+NaHS; (C, G), +Fe; (D, H), +Fe+NaHS; gl, grana lamella; S, starch; BS, bundle sheath cell; M, mesophyll cell. Bar = 0.5 µm.