Figure 2: Abnormal sperm cells induced in mice exposed to different concentrations of TiO2 NPs. (a) normal sperm cell (b) folded sperm (c) amorphous head (d) no hook (e) pin head (f) wrong tail attachment (g) sperm with double tails and amorphous head (h) sperm with double tails and short hook (i) hook at wrong angle (j) double heads with fused tails (k) knobbed hook, x1000.