Photosynthesis Flashcards
What is the Equation for Photosynthesis?
6CO2 + 6H2O + (energy) -> C6H12O6 + 6O2
What is chromatography?
A technique allowing for the isolation or separation of pure substances from a complex material. [Pigments needed for photosynthesis]
How can the Rate of Photosynthesis be Calculated?
- Oxygen production
- CO2 consumption
- Plant mass [as an indirect indication]
What is the Absorption Spectrum?
The amount of light absorbed by a pigment plotted against the wavelength of light.
What is an Action Spectrum?
A graph indicating the rate of photosynthesis at different wavelengths of light.
[Graph depicting overall photosynthetic rate at different wavelengths (colors)]
Compare the Absorption and Action Spectrums
Which Color of Light Provides the most Energy [explain]?
Short -> Violet
Exp -> Violet light has the shortest wavelength. Eventhough all waves of light carry the same amount of energy Violet waves move “faster” leading them to provide the most energy.
What is the point of having different pigments?
Increasing the rate of photosynthesis.
What are the Limiting Factors in Photosynthesis?
- Water
- Sunlight
- Temperature
- CO2
- Chloroplasts and Chlorophyll
Describe Light Intensity as a Limiting Factor in Photosynthesis
Describe Increasing Temperature as a Limiting Factor in Photosynthesis
Describe Increasing CO2 Levels as a Limiting Factor in Photosynthesis
Outline the components of Photosystems
Describe the role of Photosystems [I and II] in Light Dependant Reactions
Location -> Thylakoid of Chloroplasts
1. A light-receiving pigment in photosystem II absorbs a photon
2. Energy is transferred from pigment to pigment until it reaches the reaction center complex
3. The photon energy excites one of the chlorophylls a electrons to a higher energy state
4. This electron is captured by an electron acceptor
5. Photolysis [driven by light]-> Water is split [H, electrons, and O2] -> replace lost electrons
6. Electrons pass down electron transport chain losing energy
7. The energy lost drives chemiosmosis to bring about the phosphorylation of ADP
8. A photon is absorbed by Photosystem I and the energy is transferred through pigments until it is received by a chlorophyll a molecule
9. This electron is then accepted by an electron acceptor
10. The de-energized electron from Photosystem II replaces this electron
11. The electron is then passed down a second electron transport chain
Compare Chemiosmosis in Respiration and Photosynthesis
Describe the Calvin Cycle
Location -> Stroma of the Chloroplast
*indirectly dependent on light but called a series of light-independent reactions
1. Carbon fixation [facilitated by Rubisco] -> RuBP (5C) binds to CO2 -> unstable 6C compound
2. Split into two 3C compounds -> GP [glycerate 3-phosphate]
3. Reduction -> TP [triose phosphate]
4. Some TP leave the cycle to form sugar phosphates and become more complex carbohydrates. However, most continue to reproduce RuBP
5. ATP is used to reform RuBP from TP
