In insect spermiogenesis, mitochondrial cristae disappear and a proteinaceous material is deposited in filaments that become closely packed paracrystalline arrays. In this micrograph, crystals are pr...

Figure 423 from Chapter 16 (Cytoplasmic matrix and cytoskeleton) of 'The Cell, 2nd Ed.' by Don W. Fawcett M.D. Longitudinal section of the manchette of a rodent spermatid. The microtubules end in a ...

The events of meiosis I and II in a living insect spermatocyte beginning with the breakdown of the nuclear envelope at diakinesis through to the completion of cytokinesis. Testes from the Crane fly N...

The events of meiosis I in a living insect spermatocyte beginning at metaphase with meiotic bivalents at the spindle equator followed by anaphase , segregation of bivalents to the spindle poles and t...

Time lapse movie of meiosis in spermatocytes of the Locust Psophus stridulus showing telophase of meiosis I, cytokinesis, interphase, and prophase of meiosis II. This is a historic movie made in the...

Time lapse movie of meiosis II in spermatocytes of the Locust Psophus stridulus showing telophase and the early spermatid stage. This is a historic movie made in the early 40s by Kurt Michel of the ...

The events of meiosis I in a living insect spermatocyte beginning at metaphase I with bivalents at the spindle equator followed by anaphase, segregation of half-bivalents diakinesis and commencement o...

The events of meiosis I in a living insect spermatocyte beginning at diakinesis through telophase to the near completion of cytokinesis. Testes from the Crane fly Nephrotoma suturalis were observed wi...

The events of meiosis I in a living insect spermatocyte beginning at metaphase with meiotic bivalents at the spindle equator followed by anaphase , segregation of bivalents to the spindle poles and t...

Nuclear pores are clearly seen in these transmission electron micrographs of cells after cryo-fixation, freeze-fracture and surface replication. Upper panel shows the outer surface of of the nuclear e...