develops_from tissue lens placode ectoderm-derived structure lens vesicle (...) an essentially similar sequence of events occurs during the embryonic development of the vertebrate eye. The eye initially develops as a single median evagination of the diencephalon that soon bifurcates to form the paired optic vesicles. As each optic vesicle grows towards the body surface, its proximal part narrows as the optic stalk, and its distal part invaginates to form a two-layered optic cup. (...) The optic cup induces the overlying surface ectoderm first to thicken as a lens placode and then to invaginate and form a lens vesicle that differentiates into the lens.[well established][VHOG] A vesicle formed from the lens pit of the embryo, developing into the crystalline lens. [TFD][VHOG] EHDAA2:0000983 EHDAA:4737 EMAPA:17163 Portion of tissue that gives rise to the lens. TAO:0002205 UBERON:0005426 VHOG:0001163 ZFA:0001679 hollow lens vesicle immature lens lens mass presumptive lens solid lens vesicle the lens of zebrafish (and other teleosts) forms from delamination of cells from the lens placode; thus, there is no formation of a hollow lens vesicle, in contrast to the situation in mammals and birds (Glass and Dahm, 2004) [PMID:16496288] The lens of the zebrafish forms by delamination of lens placodal cells and not through invagination. This results in a solid spherical mass as opposed to a hollow lens vesicle. Detachment of the solid lens vesicle of zebrafish at 24b26 hpf is accomplished in part by apoptosis, similar to mammals uberon