Solved by a verified expert:Photosynthesis and Respiration
Table 1: Rf Value Comparison for Chlorophyll Pigments
Distanceto top of
# of Rf Results
to the top of the solvent front and record.
Table 2: Gross Photosynthesis
= mm of movement from
marked beginning point on bent
tube to end point after10
= mm of movement from
marked end point on bent
toward beginning point after10 minutes
(= mm Net Photosynthesis
+ mm Respiration)*
of Photosynthesis over
(= Gross Photosynthesis
÷ 10 minutes x 60 minutes)
*Was respirationoccurring during photosynthesis? Add back the O2 that was
the total photosyntheticrate.
Table 3: Comparison of PhotosyntheticRate
My PhotosyntheticRate Result
Average of Other Students’ PhotosyntheticRate
Table 4: Observationof pH Change in the Oxygen
Total timefor color
Table 5: Comparison of PhotosyntheticRate
My Result: Total
timefor color change,
Elodea, Bromothymolblue solution
Elodea, Bromothymolblue solutionin Foil
Rf = distance
of pigment in mm ÷ distance
of solvent front.
of other students’ Rf values,
ofhowfaramoleculemovedupthepaperchromatographas comparedtothelengthofthesolventfront.Thesevaluesaretypicallyequivalentformultiple trials.Calculate your
Rf values based on your paper strip results, and record them inTable 1. The Rf value of the solvent front
will always = 1.0, since Rf is
a stacked bar graph to demonstrate how
the Rf value and the chlorophyll
pigment are related.They-axiswillrepresenttheRfscalefrom0.0to1.0.Onthebargraph,labelthe
calculated Rf with the name
of the associated chlorophyll pigment.
When complete, the bar graphshouldclosely
plusanother stacked bar graphnext
graphwith your classmates’
A. Identifytheareasofpigmentsthatyouobserveonthefilterpaper.Aretheylocatedinthe order
that you expected?
If not, why not?
oftheradicchiopaper strips below. Are
the same pigments present
in radicchio leaves?
If not, which
chlorophyll pigments are missing?
you have guessed that this might be the case?
the initialhypothesis supported or
B. If you
do not see separate
bands of color on the filterpaper, what
might you conclude?
might explain why the separationof the colors occurred?
in your graph? If they are not similar, what may be the reason?
molecule was produced by
the elodea while it was exposed to
B. Which organelle(s)
in the plant cell is responsible for this reaction?
C. From where was this molecule derived?
was the purpose of the light?
E. What molecule was produced by
the elodea while it was wrapped in aluminum foil? F. Which organelle was
responsible for this reaction?
Assistant section. Compare
your Rate of Photosynthesis to
the average rates
reported by other students
in Table 3, if possible. How similar was your
result to theirs?
from that of other students or from
your own, if you repeated the experiment.
could one determine how much oxygen
is produced by the plant in one
1. From geometry,
that Volume =
ofthetube,and h = length of the movement, which means pi x radius squared x height.Sincetheradiusis½oftheinsidediameter, this
equation isequivalent to= 3.1416 x (insidediameter ofthe
bent tubein mm÷2)2
traveled) = volume
2. To convert mm3
volume to uL (typically the
volume specification used at
this level of measurement),
factor of 1
long would the plant need to
produce one liter of O2?
A. Did this experiment support or refute your
plant leaves their green color, (or red,
in the case of radicchio,
since it lacks a pigment that
is typically present in green leaves). Research light
and color, and hypothesize whetherchlorophyllabsorbsgreenlighttoanyappreciableextent.Proposeanexperimentsimilar
to the one that you just performed
that could be used to
support your hypothesis.
duetotheburning offossilfuelsandthedestruction oftherainforests(i.e.,theGreenhouse
Effect). Howdoes photosynthesis
to this controversy?
are the tropics particularlyimportant
should you support actionsthat
reduce the cuttingof rainforests?
Exercise 3: Respirationin Plants
is the elodea rinsed in distilledwater?
B. What gas did you add to
the bromothymol blue solution?
How do you know?
Respirationis our primary form of energy production.
did the color turn more green-yellow or yellow when you
D. Write an equationfor
the reactionthat explains the color change.
E. Whatcolorchangeoccurred afteryouplacedtheelodeainthetesttubeandturnedthelight source
gas is produced and responsible
for this change?
gas is being removed?
H. What process
is occurring in the firsttrial
without the aluminum foil?
I. Whatdidyouobservewhenyourepeatedtheexercisewiththetesttubecontainingthe elodea wrapped in aluminum foil?
J. What gas
What term could be applied to the second
trial? K. Which process took
(trial 1) versus when the elodea was wrapped
in aluminum foil? What might
B. Why do both plants and
in either group be possible without respiration?
C. Was the initialhypothesis supported or refuted?
without a plant present.
What explains this reaction?Howdid you
heat in this exercise?
your results similar? What
trends do you observe
the two trials?
could explain this difference?
color change and not some other factor?
H. Howdoplants,suchasPinedrops,Pterosporaandromedea,ortheGhostPlant,Monotropa uniflora,that are
not photosynthetic,make their food?
Do they respire?
What have you
learned from doing this laboratory?