Photosynthesis Lab

Materials:
       2 Beakers
       Bromothymol Blue Solution
       Water
       Aquarium Snail
       Elodea-Water Plant
    

Procedure:
      1)Begin by adding several drops of Bromothymol blue to a beaker of water. Record the results.
      2)Now add an aquarium snail to the mixture and record the results.
      3)Now create another mixture of Bromothymol blue and water and add a water plant-Elodea. Record.
      4)Finally add a water plant to the first mixture of Bromothymol blue, water and a snail.  Record the            results.  Now move the mixture into a dark room.  Record the results after 3 hours.


Results:
      1)Water plus bromothymol blue is a blue green because carbon dioxide in water produces carbonic    acid.
      2) Water plus bromothymol blue plus an aquarium snail turns yellow.  This is because Bromothylmol blue is a blue green liquid which changes to a yellow color in acid and back to blue-green when returned to a neutral pH.
     3) Water plus bromothymol blue plus elodea, an aquarium plant, is blue-green in light.  Because carbon dioxide plus water yields sugar and oxygen when chlorophyll and sun light are present.
     4) Water plus bromothymol blue plus a snail plus elodea is blue-green in light and yellow when left in the dark for three hours.  Because animals respire, green plants photosynthesize in the light and respire all the time, and sugar plus oxygen yields carbon dioxide plus water and energy.


Questions:
1) Describe exactly what effects sugar has in this lab.
2)Describe why an animal can change the color of the solution.
3)What does this lab tell us about photosynthesis?