part_of part of part of has part has part has_part bounding layer of oocyte zona pellucida UBERON:0000086 oolemma vitelline membrane ZFA:0001111 BTO:0003135 pellucid zone EHDAA2:0002220 EMAPA:16035 EHDAA:31 striated membrane zona striata A glycoprotein membrane surrounding the plasma membrane of an oocyte. It is a vital constitutive part of the latter, external but not extraneous to it. The zona pellucida first appears in multilaminar primary oocytes. zona pellucida - vitelline membrane GAID:410 NCIT:C33896 zona radiata TAO:0001111 FMA:18674 MESH:D015044 MA:0001715 Wikipedia:Zona_pellucida EHDAA:62 vitelline envelope ovary acellular membrane