Substance is like oxygen pass through the cell without the use of energy and move from an area of high concentration to an area of low concentration. This process is called

This process should be known as diffusion.

Diffusion is the process in which a substance moves from an area of high concentration to a an area of low concentration. Oxygen is a good example, like in your question, because it can have a high concentration outside the cell, and a low concentration inside the cell. And so, no energy is needed for the cell to move within the lipid bilayer.

it provides an alternative energy pathway for the reaction to proceed.

a catalyst is a substance that speeds up the rate of a chemical reaction but is not consumed during the course of the reaction.

catalysts increase the rate of reaction without being used up. they do this by lowering the activation energy needed. with a catalyst, more collisions result in a reaction, so the rate of reaction increases. different reactions need different catalysts.

a catalyst works by providing an alternative reaction pathway to the reaction product. the rate of the reaction is increased as this alternative route has a lower activation energy than the reaction route not mediated by the catalyst.