“zona”

The following 2 entries include the term zona.

zona pellucida

noun

: the transparent more or less elastic noncellular outer layer or envelope of a mammalian ovum that is composed of glycoproteins

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zona radiata

noun

: zona pellucida

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  • any of a genus helianthus especially h annuus of new world composite plants with large yellow rayed flower heads bearing edible seeds that yield an edible oil
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