Figures 22-27 in Oogenesis in Phragmatopoma (Polychaeta: Sabellariidae): Evidence for morphological distinction among geographically remote populations

Figures 22-27. Ultrastructure in Phragmatopoma caudata of the SW Atlantic. Grow Phase. Figure 22 Oocyte during early vitellogenesis (Ev) with attributes of several yolk granules (Y) and lipid droplets (Li) in the cytoplasm, adjacent to an oocyte in late vitellogenesis (Lv) which vitelline envelope (Eg) thick (1,450X). N = nucleus, arrow = clumps of heterochromatin. Figure 23 Nucleus showing the heterochromatin clumps (large white arrow) and many complex pores in the nuclear envelope (small white arrows). The perinuclear cytoplasm aspect of granular material accumulations, juxtaposed with the nuclear envelope (black arrow) and next to mitochondria (M) (2,050X). Figure 24 Small and rounded yolk granules (Y) with different electron-densities and lucid spheres are observed inside. Besides Vesicles containing some electron-dense material (white arrow) also have lucid spheres (black arrow) and resemble nascent yolk granules (8,200X). Figure 25 Yolk granules (Y) of oocytes at the beginning of vitellogenesis showing varied electron-densities (black arrow) and electron-lucent spheres (large white arrow). Glycogen is also noticed (small white arrow) (21,500X). Figure 26 Cortical cytoplasm showing Golgi complexes (GC) close to the cortical granules (CG), which are filled with a fibrous material (black arrow). Note the large amount of glycogen (Gly) in the cytoplasm (1,150X). White arrow = glycogen. Figure 27 Microvilli (Mv) are larger and the egg envelope (Eg) thicker (2), relative to the previous stage. The perivitelline space (1) appears thinner (1500X).