Answer:
To produce energy in form of ATP
Explanation:
The thylakoid membrane harbors photosystems that will receive light photons, ejecting electrons from a main chlorophyl molecule in a reaction center, to other acceptors.  These electrons will reach the electron transport chain to create a proton gradient, and subsequently, to produce ATP.  Later on these electrons will reach the other photosystem, to produce reducing power.  This is in plants.
Cyclic photosystems also exist, in some bacteria, for example,  and only produce energy as ATP.  They also have an electron transport chain.
 
        
             
        
        
        
Convection currents direct the movement of Earth's rigid tectonic plates in the planet's fluid molten mantle. 
In places where convection currents rise up towards the crust's surface, tectonic plates move away from each other in a process known as seafloor spreading.
So, I would say the answer is:
As convection currents drift across the oceans, 
they bring the pieces of Earth's crust with them as the supercontinent breaks apart.
Glad I could help, hv a good day :)
 
        
                    
             
        
        
        
Answer:
The Sun
Explanation:
The Sun is the major source of energy for organisms and the ecosystems of which they are a part. Producers, such as plants and algae, use energy from sunlight to make food energy by combining carbon dioxide and water to form organic matter. This process begins the flow of energy through almost all food webs.