What is the light dependent step in photosynthesis?

Answer 1

• The general equation for photosynthesis is :

Carbon dioxide + electron donor + light energy → carbohydrate + oxidized electron donor

2n CO2 + 2n DH2 + photons → 2(CH2O)n + 2n DO

• In oxygenic photosynthesis water is the electron donor and, since its hydrolysis releases oxygen, the equation for this process is:

carbon dioxide + water + light energy → carbohydrate + oxygen + water

2n CO2 + 4n H2O + photons → 2(CH2O)n + 2n O2 + 2n H2O

Often, 2n water molecules are cancelled on both sides, yielding:

carbon dioxide + water + light energy → carbohydrate + oxygen

2n CO2 + 2n H2O + photons → 2(CH2O)n + 2n O2