Get Affordable VMs - excellent virtual server hosting


browse words by letter
a b c d e f g h i j k l m n o p q r s t u v w x y z

thallophytamore about thallophyta

thallophyta


  2  definitions  found 
 
  From  Webster's  Revised  Unabridged  Dictionary  (1913)  [web1913]: 
 
  Thallophyta  \Thal*loph"y*ta\,  n.  pl  [NL.  See  {Thallophyte}.] 
  (Bot.) 
  A  phylum  of  plants  of  very  diverse  habit  and  structure, 
  including  the  alg[ae],  fungi,  and  lichens.  The  simpler  forms, 
  as  many  blue-green  alg[ae],  yeasts,  etc.,  are  unicellular  and 
  reproduce  vegetatively  or  by  means  of  asexual  spores;  in  the 
  higher  forms  the  plant  body  is  a  thallus,  which  may  be 
  filamentous  or  may  consist  of  plates  of  cells;  it  is  commonly 
  undifferentiated  into  stem,  leaves,  and  roots,  and  shows  no 
  distinct  tissue  systems;  the  fronds  of  many  alg[ae],  however, 
  are  modified  to  serve  many  of  the  functions  of  the 
  above-named  organs.  Both  asexual  and  sexual  reproduction, 
  often  of  a  complex  type  occur  in  these  forms.  The 
  Thallophyta  exist  almost  exclusively  as  gametophytes,  the 
  sporophyte  being  absent  or  rudimentary.  By  those  who  do  not 
  separate  the  Myxophyta  from  the  Tallophyta  as  a  distinct 
  phylum  the  latter  is  treated  as  the  lowermost  group  in  the 
  vegetable  kingdom. 
 
  From  WordNet  r  1.6  [wn]: 
 
  Thallophyta 
  n  :  used  only  in  former  classifications:  comprising  what  is  now 
  considered  a  heterogeneous  assemblage  of  flowerless  and 
  seedless  organisms:  algae;  bacteria;  fungi;  lichens  [syn: 
  {Thallophyta}] 




more about thallophyta