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Adaptations to Fulfill Basic Needs
The fleshy iris rhizome, a modified stem for food and water storage, bears adventitious roots.
A potato tuber is a modified fleshy stem bearing axillary buds, the eyes.
separated by broader internodes. Growth of leaves and flowers occurs at the expense of the corm’s total food reserves. Following flower formation, one or more new corms develop above the old organ, which eventually withers. In addition, several small corms, or cormels, may form around the stem’s base; these must grow to their full size before producing flowers. Another underground, foodand water-storage stem, formed by ginger, bamboo, calla lily, and certain species of iris, for example, is A dahlia’s root tubers store large amounts of food.
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