Photosynthesis is composed of two main parts (light-dependent and light-independent). photosystem i (ps i) and photosystem ii (ps ii) are alike in many ways. how does photosystem i and photosystem ii differ from one another?

Explanation:

PS I absorbs longer light wave length and does not deal with photolysis of water. PS II absorbs shorter light wave lengths and does deal with photolysis of water. They both send information to different primary receptors. PS I obtains electrons that flow down a electron transporter from PS II where as PS II gains electrons from water.  

the solute can move "downhill," from regions of higher to lower concentration, relying on the specificity of the protein carrier to pass through the membrane. this process is called passive transport or facilitated diffusion, and does not require energy.