The mass of a tree is primarily carbon. The carbon comes from carbon dioxide used during photosynthesis. During photosynthesis, plants convert the sun's energy into chemical energy which is captured within the bonds of carbon molecules built from atmospheric carbon dioxide and water.
        
             
        
        
        
The answer to this question is letter d. heterotrphic
The following are the choices:
<span>A) prokaryotic
B) multicellular
C) antibiotic
D) heterotrphic
</span><span>Euglenoids are freshwater protists that are both photosynthetic and </span>heterotrophic,which  means  they acquire nutrients like other animals, besides it being able to produce its own food source.
        
             
        
        
        
<span>The medical illustrations contained in this online atlas are copyrighted © 1997 by the University of Washington. They may not be utilized, reproduced, stored, or transmitted in any form or by any means, electronic or mechanical, or by any information storage or retrieval system, without permission in writing from the University of Washington. </span>
        
             
        
        
        
<span>involuntary responses are part of the autonomic system 
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