#root_hair  thin hairlike outgrowth of an epidermal cell just behind the tip; absorbs nutrients from the soil
  supertype:  plant_organ__plantorgan  a functional and structural unit of a plant or fungus
  part of:  root  the usually underground organ that lacks buds or leaves or nodes; absorbs water and mineral salts; usually it anchors the plant to the ground
     part of:  root_system__rootage  a developed system of roots

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