Photosynthesis Flashcards
What is the word equation for photosynthesis?
Carbon Dioxide + Water + Light = Glucose + Oxygen
What is the chemical question for photosynthesis?
6CO2+6H2O+Light—Chlorophyll—>C6H12O6+6O2
What is the role of photosynthesis?
- plants use it to make food
- animals get their food from plants
- photosynthesis produces oxygen
- photosynthesis has responsibility for forming fossil fuels
What are the main events in photosynthesis?
- Light is absorbed
- Water is split
- The products if splitting water
- Light energises electrons
- Glucose is formed
What happens when light is absorbed?
Sunlight that strikes a plant is trapped by the chlorophyll
What happens when the water is split?
- the trapped sunlight energy is used in the chloroplast to split water molecules
- 2H2O—>(4H+)+(4e-)+(O2)
What happens to the products of splitting water?
- the electrons are passed to the chlorophyll
- the protons are released to a storage pool of protons in the chloroplast
- the oxygen may pass out through the leaf into the atmosphere or be used within leaf cells during respiration
What happens when light energises electrons?
Sunlight energy trapped by the chlorophyll is passes on to the electrons in chlorophyll to form high-energy electrons
What happens to form glucose?
High-energy electrons from the chlorophyll, along with protons from the storage pool, are combined with carbon dioxide to form a carbohydrates (glucose)
What is a source of light?
Sunlight
What is a source if carbon dioxide?
- External: Enters the leaf from atmosphere
- Internal: respiration
What is a source of water?
Absorbed in soil through roots of plant
How can we increase the rate of photosynthesis?
- Artificial light
- Artificial sources if carbon dioxide (e.g burning gas)
- Regulate temperature (enzymes)
