Section 5:Photosynthesis Flashcards
Where does photosynthesis take place?
Chloroplasts within the leaf
What is the balanced symbol equation for photosynthesis?
6CO2+6H2O
—->C6H12O6+6O2
What do plants convert light energy into?
ATP
What are the three main stages of photosynthesis?
- Capturing light energy by chlorophyll
- The light-dependent recation
- The light-indeprendent reaction
What is chlorophyll and what is its role?
Pigment which is responsible for trapping light energy
What are the parts of the chlorophyll?
Granum,stroma,thylakoid,
thylakoid space and inner/outer membrane
What are thylakoids?
Contain the chlorophyll,enzymes and electron carriers
Site of light-dependent reaction
What are grana(granum)?
Stacks of thylakoids
What is the stroma?
The surrounding fluid containing enzymes. Site of the light-indeprendent raction
What are the two reactions involved in photosynthesis?
- Light-dependent
- Light-independent
What does the light-dependent reaction use light energy for?
To split water in order to make ATP & reduced NADP and oxygen
Why does the ligh-independent reaction stop in the absence of light?
The light-independent reaction requires the products of the light-dependent stage (ATP and reduced NADP)
What is ATP?
A form of chemical energy stored in a compound
What are the components of ATP?
Ribose (5 carbon) sugar, adenine and three phosphate groups
What is the equation involving ATP which produces energy?
ATP—>ADP+Pi+energy
What is photolysis?
Using light energy to split water
Five points
Describe how the light-dependent reaction of photosynthesis generates ATP
1.Light energy raises the energy level of electrons in the chlorophyll
2.Electrons pass down electron transfer chain
3.Electrons reduce carriers
4.Energy released
5.ATP generated from ADP and inorganic phosphate
What are the limiting factors of photosynthesis?
Carbon dioxide concentration, light intensity, water, mineral ions and temperature
How can the supply be increased for each limiting factor?
- Carbon dioxide=pump in gas or paraffin heaters
- Light intesntiy=add artifical lighting
- Temperature=use heaters to increase until optimum is reached
- Water=irrigation/sprinkler system
- Mineral ions=fertilisers (organic or inorganic)
