What happens in photo stage 1 in photosynthisis?

Consider photosynthesis at photosystem I, there electrons excited by light leave chlorophyll molecules and go through an electron transport chain. Eventually they end up in NADPH molecules.

Then consider photosystem II, it also loses light excited electrons that subsequently go through an electron transport chain. Protons get pumped out with their energy as they go through this chain, to create a proton gradient. When the protons flow back their energy is used to make ATP. The electrons finally end up in photosystem I replacing its lost electrons.

Photosystem II gets back its electrons from water by splitting it. The oxygen thus produced is released to the atmosphere.

ATP and NADPH produced in these light dependent processes are used to change carbon dioxide to glucose during the subsequent light independent reactions.

Well to put it into a nutshell

The plant starts absorbing sunlight which the plant will convert into energy for the plant to start growing:)

Growth.

growth