areole
Quick Summary
An areole is a specialized structure found on cacti, from which spines, flowers, stems, or roots grow. These small, cushion-like areas are unique to the cactus family (Cactaceae) and are essentially modified branches. In most cacti, leaves are absent or reduced to spines, and the stem takes over the photosynthetic functions. The areole is where these spines, and often flowers, develop. While the term "areola" can refer to a small area or a colored ring around something (like a nipple), in plant anatomy, "areole" specifically denotes this cactus structure.123
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cactusPhysical characteristics…plants by the presence of areoles, small cushionlike structures with trichomes (plant hairs) and, in almost all species, spines or barbed bristles (glochids). Areoles are modified branches, from which flowers, more branches, and leaves (when present) may grow.
Read More…plants by the presence of areoles, small cushionlike structures with trichomes (plant hairs) and, in almost all species, spines or barbed bristles (glochids). Areoles are modified branches, from which flowers, more branches, and leaves (when present) may grow.
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CaryophyllalesCactaceae…the presence of spines in areoles. Areoles are universal in the cactus family (at least in the juvenile phase) and have not so far been found in any other plant family. Almost all species of cactus have tufts of spines that develop from the areoles. These spines are of two…
Read More…the presence of spines in areoles. Areoles are universal in the cactus family (at least in the juvenile phase) and have not so far been found in any other plant family. Almost all species of cactus have tufts of spines that develop from the areoles. These spines are of two…
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