Chapter 10: Photosynthesis Flashcards
What is photosynthesis?
When plants absorb light for energy
- requires CO2
What are mesophyll cells?
Cells in the middle of the leaf that contain chloroplasts
Where does photosynthesis take place?
Chloroplast
What are thylakoids?
Sacs inside the chloroplast where light reactions take place
What happens in the “photo” stage of photosynthesis?
- captures energy from light
- ATP undergoes the Calvin cycle
What happens in the “synthesis” stage of photosynthesis?
- the plant makes sugar
Light energy is absorbed as a _______.
Photon
How are photons captured within a chloroplast?
By pigments on the thylakoid membrane
If a plant is absorbing red, what colour would it appear?
Green
Explain how the photosystem works.
1) Light hits the pigment molecules.
2) e- from the pigment molecules and water go to the chlorophyll molecule and then the primary e- acceptor
3) The electron transport chain begins
4) ATP and NADPH are produced
What happens to water in photosynthesis?
Converted to oxygen
Explain the transport chain of photosynthesis.
e- go to the NADP+ reductase, converting NADP+ into NADPH.
What is produced from the light reactions in the thylakoid?
ATP & NADPH
What is the Calvin cycle?
ATP and NADPH fuel the production of sugar
What are the 3 stages of the Calvin Cycle?
1) Carbon fixation
2) Reduction
3) RuBP Regeneration
What is carbon fixation in the Calvin cycle?
- Carbon from the atmospheric pressure is taken to form biomolecules.
- Requires ATP.
- 3 CO2 per cycle
What is reduction in the Calvin cycle?
- Biomolecules converted to sugar
- Requires NADPH
What is RuBP Regeneration?
The protein, rubisco, is regenerated to continue the Calvin cycle.
What would happen to the light reactions if the Calvin cycle enzyme, rubisco, was inhibited?
The light reactions would be inhibited because of a lack of NADP+ and ADP.
What must the Calvin cycle do in order to keep photosynthesis going?
Give back NADP+ and ADP.
Quickly, what happens in the chloroplasts vs the mitochondria?
- Chloroplasts use energy to make sugar
- Mitochondria converts sugar into energy
Explain the electrochemical gradient in photosynthesis.
There are H+ ions floating inside the thylakoid space. They go through ATP synthase and produce ATP outside of the thylakoid (the stroma).
- the ATP then goes to the Calvin cycle
