====== BIOLOGY TREE BASE ======

  * Biology tree 
    * anatomical trees 
      * linear stems with no branches 
      * branching trees 
        * [[:en:respiratory_tree | respiratory tree ]]
        * [[:en:arterial_tree | arterial tree ]]
        * [[:en:venous_tree | venous tree ]]
        * [[:en:neural_tree | Neural tree ]]
    * Disease Trees ( following the anatomical paths )
      * cancer tree
      * infections tree