BIOL 1107L
Photosynthesis
Photosynthesis
Pre-Lab Objectives
These objectives should be completed and entered into your laboratory notebook before
coming to lab. This information will be helpful for any lab quizzes/exams and is expected to be
in your notebooks during notebook checks.
You will be doing Exercises 2, 3, and 4. You will write a lab report on Exercise 3 and 4 following
the posted rubric after completing the lab.
Introduction
1. What is the source of energy for photosynthesis?
2. What is the site of photosynthesis in eukaryotic cells?
3. What is the general formula for photosynthesis?
4. Why can starch be used as a measure of photosynthesis?
5. Briefly (in a few sentences or paragraph), write a general overview of photosynthesis.
Exercise 2
6. Define pigment. What is the function of pigments in photosynthesis?
7. What wavelengths of light are absorbed or reflected by white, black, and the other colors of
the visible spectrum?
8. What is the relationship of absorption and reflection of light with its usefulness in
photosynthesis?
9. What is the purpose of this experiment?
10. Formulate a hypothesis for this experiment. (Keep in mind that the hypothesis must be
testable using the experiment in the book.)
11. Make a prediction statement for the experiment based on your hypothesis.
12. What is the purpose of I2KI in this experiment?
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BIOL 1107L
Photosynthesis
Exercise 3
13. Discuss the principles of paper chromatography:
How do you set up the chromatography?
Why do the pigments separate as they migrate up the paper?
How can the solubility of the pigments be determined?
What order would you expect chlorophyll a, chlorophyll b, beta carotene, and xanthophylls be
in this experiment?
14. What is the purpose of this experiment?
15. Formulate a hypothesis for this experiment. (Keep in mind that the hypothesis must be
testable using the experiment in the book.)
16. Make a prediction statement based on your hypothesis.
Exercise 6.4
17. Define absorption spectrum. What information can we learn from an absorption spectrum?
18. How does the spectrophotometer measure percent transmittance (%T)? What is percent
transmittance? What is the purpose of the blank? (you should have these written down from
last week, so please refresh your memory).
19. State the purpose of the experiment.
20. Formulate a general hypothesis for this experiment. (Keep in mind that the hypothesis must
be testable using the experiment in the book.) You probably don’t know what wavelengths of
light each pigments absorb, but you could make some general statements if you know what
color the pigments are.
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