egg membrane


egg mem·brane

, secondary egg membranetertiary egg membranethe investing envelope of the oocyte; a primary egg membrane is produced from ovarian cytoplasm (for example, a vitelline membrane); a secondary egg membrane is the product of the ovarian follicle (for example, the zona pellucida); a tertiary egg membrane is secreted by the lining of the uterine tube (for example, a shell).

egg mem·brane

, secondary egg membrane , tertiary egg membrane (eg mem'brān, sekŏn-dar-ē, tĕrshē-ăr-ē) A primary egg membrane is produced from ovarian cytoplasm (e.g., a vitelline membrane); a secondary egg membrane is the product of the ovarian follicle (e.g., the zona pellucida); a tertiary egg membrane is secreted by the lining of the oviduct (e.g., a shell).

egg membrane

Any of the protective membranes or envelopes enclosing an ovum. It may be primary (formed by egg itself, as in vitelline membrane), secondary (formed by follicle cells, as in zona pellucida), or tertiary (formed by oviduct or uterus, as in albumin and shell of hen's egg). See also: membrane

egg membrane

any membrane, shell or jelly-like layer surrounding and protecting the EGG, including primary membranes secreted by the OVUM or OOCYTE, secondary membranes secreted by cells of the ovary and tertiary membranes, for example albumen and egg shell, secreted by glands of the oviduct.