When the excited electron reaches the special chlorophyll molecule at the reaction centre of Photosystem II it is passed on to the chain of electron carriers.
This chain of electron carriers is found within the thylakoid membrane.
As this excited electron passes from one carrier to the next it releases energy.
ATP synthase is located in the thylakoid membrane and it uses the energy released from the movement of protons down their concentration gradient to synthesise ATP from ADP and inorganic phosphate.
The synthesis of ATP in this manner is called non-cyclic photophosphorylation (uses the energy of excited electrons from photosystem II) .
The electrons from the chain of electron carriers are then accepted by Photosystem I.
Figure 8.2.1 - Chloroplast Photosynthesis consists of light-dependent and light-independent reactions. Chloroplasts contain chlorophyll, a green pigment found inside the thylakoid membranes.
These chlorophyll molecules are arranged in groups called photosystems.
There are two types of photosystems, Photosystem II and Photosystem I.When a chlorophyll molecule absorbs light, the energy from this light raises an electron within the chlorophyll molecule to a higher energy state.The chlorophyll molecule is then said to be photoactivated.Excited electron anywhere within the photosystem are then passed on from one chlorophyll molecule to the next until they reach a special chlorophyll molecule at the reaction centre of the photosystem.This special chlorophyll molecule then passes on the excited electron to a chain of electron carriers.The light-dependent reactions starts within Photosystem II.