A2 Biology- Photosynthesis

PHOTOSYNTHESIS

6CO2 + 6H20 -----> C6H1206 + 6CO2

• Carbon dioxide is reduced (loses electrons) as hydrogen and electrons from water are added to it, creating a carbohydrate. 
• The reactions in photosynthesis require an input of energy- LIGHT. 
• This energy needed to break bonds within carbon dioxide and water is greater than the energy released when glucose and oxygen are formed, therefore the products of the reaction are at a higher energy level than the reactants. These act as a store of energy.
• Oxygen is a waste product, glucose is a fuel.
• Hydrogen is separated from water and stored within a carbohydrate. When energy is required in the cell, the hydrogen stored in the carbohydrate reacts with oxygen during respiration, releasing a large amount of energy.

Photolysis is the splitting of water into hydrogen and oxygen. This requires energy from the sun. 

The hydrogen reacts with carbon dioxide in order to 'store' the hydrogen. Carbon dioxide is reduced to form the carbohydrate fuel glucose, which can be stored or …