zona pellucida
(noun)
a glycoprotein membrane surrounding the plasma membrane of an oocyte
Examples of zona pellucida in the following topics:
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Fertilization
- In mammals, the egg is protected by a layer of extracellular matrix consisting mainly of glycoproteins called the zona pellucida.
- When a sperm binds to the zona pellucida, a series of biochemical events, called the acrosomal reaction, take place.
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Adrenal Glands
- These layers form three distinct regions: an outer zona glomerulosa that produces mineralocorticoids; a middle zona fasciculata that produces glucocorticoids; and an inner zona reticularis that produces androgens, which are sex hormones that promote masculinity.