Fig. 8

Representative transmission electron micrographs of A. pegreffii proximal oviduct encompassing the following: a Late oocytes with many large electron-light and depleted granules, small spherical and depleted refractile bodies, and electron-dense, vermiform mitochondria. Note a central large nucleus with prominent nucleolemma. b Oocytes excreting a lipid/proteinaceous substance in the oviduct lumen from its electron-light granules (black arrows). c Refractile bodies enveloped by a double membrane of the Golgi apparatus (white arrowhead) with depleted fibrillar content (white asterisk), and mitochondria (m). d Electron-dense oocytes with central nucleus and nucleolus, lacking a prominent nucleolemma. Note denser refractile bodies in its cytoplasm and lack of electron-light large granules. These rarely occurring cells were found in close contact via short pseudopodia to the sheathe cells (sc) in the basal lamina (bl). e Refractile body filled with fibrillar electron-dense material (in transverse section; white asterisk) enveloped in a membrane of the Golgi apparatus (white arrowhead), in proximity of a mitochondrion (m). f Periphery of the electron-dense oocyte with a pseudopodial projection and Golgi apparatus forming a refractile body (white arrow). g Cross section of the oviduct basal lamina (bl) with a single-cell layer of sheath cell. Note the spherical nucleus and large electron-light granules. h Bundles of myofibrils in cross section (black asterisk) and longitudinal section, surrounding a mitochondrion within a sheath cell. i Conspicuous multi-lamellar bodies (black arrowhead) forming in the cytoplasm of a sheath cell lining the basal lamina (bl). Scale bars: 5 µm (a, b, d); 2 µm (g, i); 500 nm (c, h, f); 200 nm (e)