Opening flower bud of the opium poppy (Papaver somniferum). The developing flower bud is covered by a protective sheath comprised of two sepals (here

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Opening flower bud of the opium poppy (Papaver somniferum). The developing flower bud is covered by a protective sheath comprised of two sepals (here pale yellow-green). The petals (red)are tightly packed together and crumpled. As the bud expands, the sepals detach themselves from base of the flower by a process of abscission. Further enlargement of the bud causes the sepals to fall from the flower, leaving the petals free to expand into their familiar uncrumpled form. This process is achieved by an increase in osmotic pressure within the petal cells caused by the hydrolysis of starch into sugars

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Size: 3413px × 5121px
Photo credit: © DR JEREMY BURGESS/SCIENCE PHOTO LIBRARY / Alamy / Afripics
License: Licensed
Model Released: No

Keywords: abscission, biological, biology, botanical, botany, bud, flower, hydrolysis, opium, osmotic, papaver, petals, poppy, pressure, sepals, somniferum, starch