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September 21, 2004; 101 (38)
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Cover image: Opium poppy (Papaver somniferum) capsule. Opium poppy is the commercial source of the narcotic analgesics morphine and codeine. These drugs accumulate in specialized internal secretory cells called laticifers. In poppy capsules, laticifers form a three-dimensional network from which milky white latex (opium) exudes when the plant is incised. See the article by Weid et al. on pages 13957–13962. Photograph courtesy of Toni Kutchan.

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September 21, 2004; 101 (38)
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