11 Photosynthesis Flashcards
Define photosynthesis
Is the process by which green plants produce glucose and oxygen from carbon dioxide and water.
What is the catalyst in this process
The green pigment called chlorophyll
Balanced ewuation to show photosynthesis
Chlorophyll
6C02+6H20+light———>C6H12O6+6O2
Role of Photosynthesis
-Plants use it to make food
-Animals get food from plants
-Produces oxygen for use in respiration
-Responsible for forming fossil fuels
5 Main events in photosynthesis
1.Light is absorbed
2.Water is split
3.Products of splitting water
4.Light energises electrons
5.Glucose is formed
1.How is the light absorbed in photosynthesis
Sunlight strikes a plant and is trapped by chlorophyll in the chloroplast.
The trapped sunlight provides the energy a plant needs to make glucose
Where in the cell does photosynthesis take place
Chloroplast
2.How is water split in photosynthesis
Some of trapped sunlight energy is used in the chloroplast to split water molecules
When two water molecules are split they form 4 protons 4electrons and a molecule of oxygen gas
What are the three products formed when water is split
Protons (H+)
Electrons (E-)
Oxygen (O2)
What happens to the electrons after water is split
The electrons are passed to chlorophyll
What happens to protons after water is split
Protons are released into a storage pool of protons in the chloroplast for later use
What happens to oxygen after water is split
oxygen may pass from the chloroplast out into the cytoplasm and eventually out of the leaf into the atmosphere
Alternatively the oxygen may be used within the cells of the leaf in the process of respiration
4.What happens when light wnergises electrons
Some of the sunlight energy trapped by chlorophyll is passed on to electrons in chlorophyll to form high-energy electrons
5.How is glucose formed
The high energy electrons from chlorophyll along with protons from the pool of stored protons are combined with CO2 to form a carbohydrate:(glucose, C6 H12 O6)
