Eyelids, Biology

EYELIDS -

  • 3 in number. Dermis is thinnest in it. Upper and lower eye lid with eye lashes. Upper eye lid is more motile
  • In reptiles lower eye lid is more motile. In cyclostomate, bonny fishes eye lids are absent.
  • In snakes eye lids are immovable. Third one is nictitating membrane which is thin & transparent.
  • In man it is vestigeal know as Plica seminularis. Nictitating membrane of sharks & frogs is prolongation of lower eye lid.
Posted Date: 10/3/2012 3:21:25 AM | Location : United States







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