Professional
Technical
In the Industry Vocabulary Test
Zona Pellucida
Pronunciation: ZOH-nuh peh-LOO-si-duh
The glycoprotein shell surrounding a mammalian oocyte that sperm must penetrate for fertilization.
Full Definition
The zona pellucida is a thick, transparent membrane composed of glycoproteins that surrounds the oocyte and early embryo. In assisted reproduction, its thickness and integrity are important factors in embryo assessment. Laser-assisted hatching may be performed to thin this layer and improve implantation rates. The zona pellucida also plays a crucial role in preventing polyspermy and maintaining embryo integrity during early development.
Usage
Usage note: Often abbreviated as ZP in laboratory documentation.
In Context
- "The embryologist noted an unusually thick zona pellucida requiring assisted hatching before transfer." — Laboratory report
- "Zona pellucida hardening occurred after cryopreservation, necessitating laser assistance." — Treatment protocol
Also known as
ZP
Don't confuse with
zona radiata
corona radiata