Nectaries by bestofsharm

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									 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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