yolk sphere

yolk sphere

See morula.
References in periodicals archive ?
Each squamous epithelial cell possessed a single, ovoid nucleus, and the ooplasm was relatively homogeneous, showing no evidence of yolk spheres.
Although we have not demonstrated that trypan blue becomes incorporated into membrane bound yolk spheres as does Vg, it is reasonable to assume that this is the case since only terminal follicles in each ovariole sequester the dye and since the dye colocalizes with Vg in the spaces between follicle cells (Fig.