Hoplonemertea

Spermatozoa (arrowhead) occurring in the connective tissue compartment directly outside an ovary. hi, basal lamina; inc...Spermatozoa (arrowhead) occurring in the connective tissue compartment directly outside an ovary. hi, basal lamina; inc, lateral nerve cord; sc, somatic cell; VO, vitellogenic oocyte. Scale bar, 1 u.m.

A fertilized zygote within the lumen of an ovary. The double arrowheads point to an electron-dense egg membrane....A fertilized zygote within the lumen of an ovary. The double arrowheads point to an electron-dense egg membrane. hi, basal lamina. Scale bar, 10 u.m.

Photomicrograph of a compressed female worm with cleaving embryos in its ovaries (double arrowheads). Scale bar, 50 u.m.

The apical surface of a vitellogenic oocyte (va) that is surrounded by somatic cells (se) with basally located tubular elements.The apical surface of a vitellogenic oocyte (va) that is surrounded by somatic cells (se) with basally located tubular elements. The double arrowheads mark a putative endocytotic vesicle. lu, lumen of ovary; mv, microvilli. Scale bar, 1 u.m.

The border between a vitellogenic oocyte (vo) and a somatic cell (se) with numerous tubular elements. Some of the tubules...The border between a vitellogenic oocyte (vo) and a somatic cell (se) with numerous tubular elements. Some of the tubules seem to fuse with the oolemma (arrowhead). hi, basal lamina. Scale bar, 1 um. Inset: several tubules (arrowheads) apparently in the process of fusing to the oolemma of a vitellogenic oocyte (vo). se, somatic cell. Scale bar, 0.5 um.

Basal infoldings and the vesicular to tubular elements (double arrowheads) that apparently become incorporated in the somatic...Basal infoldings and the vesicular to tubular elements (double arrowheads) that apparently become incorporated in the somatic cell (se) . Note the numerous dense particles directly outside the basal lamina (hi). Scale bar, 1 um.

The border between the ovary and intestine. Numerous electron-dense particles (double arrowheads) occur in the narrow...The border between the ovary and intestine. Numerous electron-dense particles (double arrowheads) occur in the narrow extracellular space between the basal laminae (hI) of theovary and intestine. The single arrowheads mark tubular elements occurring within the basal region of a somatic cell. ie, intestinal cell; ser, smooth endoplasmic reticulum. Scale bar, 1 um. Inset: higher magnification view of a tubular vesicle (arrowhead) attached to the inner surface of the basal lamina (hI). Scale bar, 100 nm.

An adintestinal somatic cell (sc). The double arrowheads mark peculiar clusters of nuclear bodies, and the single arrows point..An adintestinal somatic cell (sc). The double arrowheads mark peculiar clusters of nuclear bodies, and the single arrows point to infoldings of the basal lamina. id, intestinal diverticulum; ly, lysosome; 00, oocyte. Scale bar, 10 urn.

Large yolk bodies with plaques (p) in their internal regions (arrowheads). Scale bar, 1 um.

Plaquelike inclusions (p) that seem to fuse with electron-dense material during yolk formation. Scale bar, 1 um.

Stacks of plaque like inclusions (p) apparently in the process of forming ovoid bodies. Scale bar, 1 um

A membrane-bound yolk granule (gr) and nascent plaquelike bodies (p) being formed in the vicinity...A membrane-bound yolk granule (gr) and nascent plaquelike bodies (p) being formed in the vicinity of the rough endoplasmic reticulum. The double arrowheads mark an apparent fusion between a granule and lipid droplet. Scale bar, I J.Lm.

Stages in yolk formation. The arrows mark vesicular components of developing yolk bodies. p, plaque. Scale bar, 1 um.

A diagram of an ovary showing various stages of oogenesis...A diagram of an ovaryshowing variousstagesof oogenesis andthe relationship between germinal and somaticcells in the ovarian epithelium. I, oogonium or a young previtellogenic oocyte; II, a previtellogenic oocyte; III, an early vitellogenic oocyte; IV, a late vitellogenic oocyte; V, a yolk-filled oocyte in the process of being moved intothe lumenof the ovary;VI, a primaryoocytein the ovarian lumen. hi, basallamina; m, myofilaments; n, nucleus; SC, somatic cell.

Stubby microvilli (mv) arising from a primary oocyte (00) in the lumen of the ovary. The apical surface of the ovarian...Stubby microvilli (mv) arising from a primary oocyte (00) in the lumen of the ovary. The apical surface of the ovarian epithelium is depicted at the bottom of the micrograph. Note that the oocyte lacks well developed extracellular coats or surrounding follicle cells. Scale bar, 1 urn.

15. A primary oocyte (00) in the lumen of the ovary. The double arrows point to patches of dense material that may represent...A primary oocyte (00) in the lumen of the ovary. The double arrows point to patches of dense material that may represent parts of a poorly developed vitelline envelope. sc somatic cell. Scale bar, 10 um.

A junctional complex (jc) adjoining an oocyte (00) and its neighboring somatic cell (sc). Scale bar, 1 um

primary oocyte (00) in the lumen of the ovary (lu). bl, basal lamina; gv, germinal vesicle; sc, somatic cell. Scale bar, 10 urn.

An oocyte (00) in the process of being moved into the ovarian lumen (lu). Membranous lamellae (arrowhead) can be seen attached..An oocyte (00) in the process of being moved into the ovarian lumen (lu). Membranous lamellae (arrowhead) can be seen attached to the inner surface of the nuclear envelope. bl, basal lamina; n, nucleus. The box outlines the region shown at higher magnification in Fig. 14. Scale bar, 10 micrometers.

Oocytes at early (evo) and late stages of vitellogenesis (Ivo). The double arrowheads mark the border between two oocytes...Oocytes at early (evo) and late stages of vitellogenesis (Ivo). The double arrowheads mark the border between two oocytes. bl, basal lamina. Scale bar, 5 micrometers.

Vitellogenic oocyte (vo) that abuts the ovarian lumen. The double arrowheads point to apical processes of somatic cells...Vitellogenic oocyte (vo) that abuts the ovarian lumen. The double arrowheads point to apical processes of somatic cells, and the single arrow marks microvilli arising from the oocyte. 00, oocyte in lumen. Scale bar, 5 micrometers.

A rare example of annulate lamellae (aI) in a vitellogenic oocyte. p, plaque. Scale bar, 1 micrometer.

Various inclusions within a vitellogenic oocyte...Various inclusions within a vitellogenic oocyte. l, lipid; p, plaque; rer, rough endoplasmic reticulum; vb, vesicular body. Scale bar, 1 micrometer.

The ovarian epithelium with two vitellogenic oocytes. The double arrows mark the nucleus of one of the oocytes...The ovarian epithelium with two vitellogenic oocytes. The double arrows mark the nucleus of one of the oocytes, and the single arrow points to somatic cell processes. lu, lumen of ovary; 00, oocyte in lumen. Scale bar, 10 micrometers.