Photosynthesis Flashcards
What is the equation for photosynthesis?
6CO2 + 6H2O + light energy → C6H12O6 + 6O2
What are the main functions of chloroplasts?
- To absorb light energy to drive photosynthesis.
- To convert light energy into chemical energy.
What are thylakoids?
Flattened sacs that contain pigments in their membranes to absorb light for the light dependent reaction.
What are grana?
Stacks of thylakoids
What are lamellae?
Membranous extensions that connect thylakoids
What is the stroma?
A fluid surrounding the thylakoids where the light independent reaction occurs.
What are chloroplast DNA used for?
Contain the genes that code for proteins involved in photosynthesis.
What is Chlorophyll a?
The main pigment that absorbs red and blue light and reflects green.
What is chlorophyll b?
An accessory pigment mostly found with chlorophyll a in light-harvesting complexes.
What are xanthophylls and carotenoids?
Absorb different wavelengths than chlorophyll, broadening the spectrum of light that can drive photosynthesis.
What are clusters of pigments called and where are they found?
Photosystems.
Found in the thylakoid membranes.
What does each photosystem have?
A light harvesting system that absorbs light energy which is then transferred to a reaction centre. This emits high energy electrons to drive light dependent reactions.
What is photophosphorylation?
Where ATP is formed using light energy.
What is non-cyclic photophosphorylation?
The use of water and light energy to produce ATP, reduced NADP and oxygen.
Describe the first stage in non-cyclic photophosphorylation?
- Light energy is absorbed by pigments.
- This excited electrons in the pigments in photosystem 1 and photosystem 2 reaction centres.
- Electrons are lost from the pigments.