Light micrograph of a sessile secretory gland on the herb sweet marjoram, Origanum majorana. There are two basic types of secretory glands (or trichom

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Light micrograph of a sessile secretory gland on the herb sweet marjoram, Origanum majorana. There are two basic types of secretory glands (or trichomes); stalked and unstalked (or sessile). A number of variations of structure exist but generally between 4 and 12 specialised cells form a small cushion over which a membrane develops. Each cell produces and secretes a cocktail of oils which accumulate beneath the membrane causing it to swell. Plants usually secrete extrafloral substances as a defence against bacteria, fungi or predators. Floral secretions attract insects for pollination purposes. Magnification: x400 at 35mm size.

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Size: 5072px × 3472px
Photo credit: © POWER AND SYRED/SCIENCE PHOTO LIBRARY / Alamy / Afripics
License: Licensed
Model Released: No

Keywords: botany, gland, herb, image, images, leaf, leaves, light, magnified, majorana, marjoram, micrograph, microscopic, nature, origanum, photos, plant, plants, secretory, subjects, trichome