Photosynthesis Worksheet
Light-Dependent Reactions:
! 1.! Where in the chloroplast do the light-dependent reactions occur?
! 2.!
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! 3.!
! !
! !
! !
What light absorbing molecules are present in photosystem II and I?
Discuss what happens to the following three things when water is split:
! O2:
! 2H+:
! 2e-:
! 4.! What is happening to the 2H+ as the high energy electrons are being passed from
! ! photosystem II to photosystem I?!
! 5.! When 2H+ moves through the ATP synthase protein channel ATP is formed
! ! from ADP + P. Why do the 2H+ move in the direction they do as shown on the
! ! diagram?
! 6.! What are the two energy rich molecules produced in the light-dependent
! ! reactions? Where do they go?
Photosynthesis Worksheet
Light-Independent Reactions (a.k.a. Calvin Cycle):
! 1.! Where in the chloroplast do the light-independent reactions occur?
! 2.! What three things are put in to the Calvin cycle?
! 3.! What one thing is put out of the Calvin cycle?
! 4.! Do the math: there are 3 five-carbon molecules of RUBP and 3 six-carbon
! ! molecules of Rubisco. Where do the extra carbons come from? How many of
! ! them are needed?
Photosynthesis Worksheet
! 5.! Glyceraldehyde-3-phosphate or G3P is a high energy chemical. From where did
! ! the energy come from to form G3P?
! 6.! Do the math: G3P is a 3-carbon carbohydrate. How many turns of the Calvin cycle
! ! are needed to produce one glucose molecule?
Checking Your Understanding:
! 1.! List any external factors that may affect photosynthesis:
! 2.! Explain why the reactions of Calvin cycle are called the “light-independent
! ! reactions”.
! 3.! In has been determined that plant CO2 uptake is highest during peak hours of day
! ! light. Taking the explanation from number 2 into consideration, explain why this
! ! would be the case.
! 4.! In the 1700s Jan Ingenhousz showed that air is restored when the green parts of a
! ! plant are exposed to sunlight. What is Ingenhousz referring to when using the
! ! word “restore”?
! 5.! In the 1600s Jan Baptista van Helmont tried to prove that all of a plant’s nutrients
! ! came from the soil. After weighing both the seedling (baby plant) and the pot of
! ! soil he planted the tree. Five years later the plant gained 164 pounds but the pot
! ! of soil lost only 2 ounces. Based on your understanding of photosynthesis, from
! ! where did the plant get its nutrients to grow?
! 6.! To maintain healthy plants and a successful business, what three factors must an
! ! owner of a greenhouse monitor?!
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