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How to make a pinecone open and close
Description
Discover the fascinating mechanism that allows pinecones to protect their seeds by responding to changes in environmental humidity. Through a simple experiment using hot and cold water, you can observe how the scales open and close, revealing the physical phenomenon that enables the tree to disperse its seeds only under dry conditions.
Original title
איך לגרום לאצטרובל להיפתח ולהיסגר?
גלו את המנגנון המרתק שמאפשר לאצטרובלים להגן על הזרעים שלהם באמצעות תגובה לשינויי לחות בסביבה. בעזרת ניסוי פשוט במים חמים וקרים, תוכלו לראות כיצד הקשקשים נפתחים ונסגרים, ולהבין את התופעה הפיזיקלית המאפשרת לעץ להפיץ את זרעיו בתנאים יבשים בלבד.
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