Answer:
Some materials are so important to a cell that it spends some of its energy (hydrolyzing adenosine triphosphate (ATP)) to obtain these materials. ... Passive transport is a naturally-occurring phenomenon and does not require the cell to exert any of its energy to accomplish the movement.
Explanation:
Passive transport is a type of membrane transport that does not require energy to move substances across cell membranes. ... The four main kinds of passive transport are simple diffusion, facilitated diffusion, filtration, and/or osmosis.
