Final answer:
The movement of materials as indicated in the diagram is related to active transport, an energy-requiring process where substances move against a concentration gradient with the help of transport proteins.
Step-by-step explanation:
The movement of materials indicated by the arrows in the diagram is most directly involved in the process of active transport. Active transport refers to the energy-dependent movement of substances across a cell membrane from an area of lower concentration to an area of higher concentration, counter to the direction expected by diffusion. This process relies on cellular energy, usually in the form of ATP, and involves specific transport proteins that function as pumps to facilitate the movement of molecules against their concentration gradient.