Morphological analyses of Spatc1l-KO epididymal sperm by SEM. Sperm were obtained from the vas deferens of 8-week-old WT (Spatc1l+/+) and KO (Spatc1l-/-) mice. Sperm neck regions are magnified in lower panels. AC, acrosomal cap; MP, mid piece; BP, basal plates. Scale bar = 2 μm (upper) and 0.5 μm (lower). 