SEM analysis of marine invertebrate gametes

Scanning electron microscopy (SEM) enables a close-up investigation of topographical features at the cellular level down to a resolution of about 3 nm. In terms of gametes this allows for examination of minute surface details and changes that occur during fertilization. Sometimes these features are hidden from view and must be carefully exposed during preparation in order to be made visible in the SEM. This chapter describes methods that can reveal surface details of gametes for observation, as well as fix them permanently, while keeping fixation artifacts to a minimum.