Pyrena - définition. Qu'est-ce que Pyrena
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Qu'est-ce (qui) est Pyrena - définition

THE STONE WITHIN A DRUPE, CONTAINING THE SEED SURROUNDED BY HARD ENDOCARP TISSUE
Fruitstone
  • Diagram of a typical drupe, in this case a [[peach]], illustrating the layers of both the fruit and the seed; the pyrene is the hardened [[endocarp]] which encloses the [[seed]]

Pyrena         
·noun A nutlet resembling a seed, or the kernel of a drupe.
Pyrena         
A pyrena or pyrene (commonly called a "pit" or "stone") is the fruitstone within a drupe or drupelet produced by the ossification of the endocarp or lining of the fruit. It consists of a hard endocarp tissue surrounding one or more seeds (also called the "kernel").

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Pyrena

A pyrena or pyrene (commonly called a "pit" or "stone") is the fruitstone within a drupe or drupelet produced by the ossification of the endocarp or lining of the fruit. It consists of a hard endocarp tissue surrounding one or more seeds (also called the "kernel"). The hardened endocarp which constitutes the pyrene provides a protective physical barrier around the seed, shielding it from pathogens and herbivory.

While many drupes are monopyrenous, containing only one pyrene, pome-type fruit with a hard, stony (rather than leathery) endocarp are typically polypyrenous drupes, containing multiple pyrenes.