Photosynthesis Flashcards
ATP is useful in many biological processes. Explain why (5)
- Releases energy in small amounts
- Broken down in one step / single bond broken
- Immediate energy compound
- Phosphorylates
- Makes more reactive / lowers Ea
- Can be reformed / made again
Contrast the structures of ATP and a nucleotide found in DNA to give two differences (2)
- ATP has ribose sugar whereas DNA nucleotides have deoxyribose sugar
- ATP has 3 phosphate groups whereas DNA nucleotides have only 1 phosphate groups
- ATP nitrogen-containing base is always adenine whereas DNA nucleotide base can differ (adenine, thymine, guanine, cytosine)
Give two ways in which the hydrolysis of ATP is used in cells (2)
- Active transport of Na+
- Phosphorylates other compound making them more reactive
- Releases small amounts of energy for protein synthesis
- DNA replication
- Secretion of enzyme / hormones
Where does the light-dependent reaction occur? (1)
Granum
Where does the light - independent reaction occur? (1)
Stroma
Name the two products of the light - dependent reaction that are required in the light - independent reaction? (2)
- ATP
- NADPH
What are the reactants and products of the light - dependent reaction? (2)
- REACTANTS - Light, Water
- PRODUCTS - Oxygen, ATP, NADPH
What are the reactants and products of the light - independent reaction? (2)
- REACTANTS - NADPH, ATP, Carbon Dioxide
- PRODUCTS - Glucose
What does a co-enzyme do? Give an example (1)
Co-operates with an enzyme
Example - NADPH
What is meant by the photo-ionisation of chlorophyll? (1)
Oxidation of Chlorophyll when hit by light
What is meant by photo-lysis of water? (1)
Splitting of water to produce 2 electrons, 2 protons and half O2
What is meant by the photo-phosphorylation of ADP? (1)
making ATP (from ADP + Pi) using energy from light
Describe the light dependent reaction (6)
- Chlorophyll absorbs light energy and excites electrons
- Electrons removed (Oxidation of chlorophyll) via photo-ionisation
- Electrons move along carriers/electron transport chain releasing energy
- Energy released (by electrons) used to form proton gradient
- H+ ions move through ATP synthase
- Providing energy to join ADP and Pi to form ATP
- Photolysis of water produces 2 protons, 2 electrons and ½ Oxygen
- NADP reduced by electrons and protons / H+
Describe the light independent reaction. (6)
- Carbon dioxide combines with RuBP
- Produces two GP with enzyme RuBisCo
- GP reduced to triose phosphate
- Using NADPH
- Using energy from ATP
- Triose phosphate converted to glucose or RuBP
Where precisely is RuBisCo found in a cell? (1)
Stroma