vitelline membrane

American  

noun

1. the membrane surrounding the egg yolk.

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vitelline membrane British  

/ vɪˈtɛlɪn, -aɪn /

noun

1. zoology a membrane that surrounds a fertilized ovum and prevents the entry of other spermatozoa

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Etymology

Origin of vitelline membrane

First recorded in 1835–45

Example Sentences

They observed that interactions between the embryo and the vitelline membrane provided a source of mechanical force.

From Nature

The human ovum is a flattened spherical cell, made up of a very delicate cell-wall, called the vitelline membrane; outside this is a comparatively thick membrane, the zona pellucida, which is properly not a part of the cell.

From Project Gutenberg

The eggs are small; the diameter of recently-deposited eggs is about 1.3 mm. and that of the vitelline membrane is about 1.5 mm.

From Project Gutenberg

The only membrane enclosing the individual eggs is the vitelline membrane.

From Project Gutenberg

This new individual at first is simply a uninucleated mass of living matter, which always contains a certain amount of food-yolk, and is generally bounded by a delicate cuticular membrane called the vitelline membrane.

From Project Gutenberg