Nectaries are structures that secrete nectar, a sugary exudate that attracts insects, birds, or other animals. Most nectaries are associated with flowers and are called floral nectaries. Their nectar is 10%-50% sugar (especially sucrose, glucose, and fructose) and also contains amino acids. Nectar typically is pushed or diffuses through the walls of secretory cells, but may also ooze from the stomata. Nectar in floral nectaries attracts insects and other animals that pollinate the plant. Plants usually secrete small amounts of nectar, which forces foraging animals to visit several flowers before getting a full meal. Thus, a single animal can pollinate tens or hundreds of plants. Nectaries that occur on vegetative parts of plants are called extrafloral nectaries. This nectaries often attract animals that defend the plant. For example, the extrafloral nectaries of plants such as trumpet creeper (Campsis radicans) and Costus attract ants that eat the nectar and, in return, defend the plant from leaf-eating insects. Thesetiny defenders are surprisingly effective: Costus plants deprived of ants are quickly devastated by fly larvae, and produce only one-third as many seeds as plants protected by ants. HAVE A NICE DAY !
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