Which process is characterized by the movement of particles from an area of high concentration to an area of low concentration across the plasma membrane without the use of energy? 1) hypertonic transport
2) active transport
3) passive transport
4) dynamic equilibrium

3) passive transport

Explanation:

Passive transport is a type of cellular transport that does not require the use of energy to move substances (i.e., ions and molecules) across biological membranes. Passive transport uses concentration gradients to move substances across cell membranes, thereby transporting them from regions of high concentration to regions of low concentration. Passive transport can be divided into 1-osmosis (i.e., movement of solvents), 2-diffusion (i.e., movement of solutes), and 3-facilitated diffusion (i.e., movement of molecules with help of protein channels or carriers), and 4-filtration (i.e., movement of water by using a pressure gradient).

many other transport proteins, often called pumps, move materials against a concentration gradient. active transport drives molecules across a membrane from a region of lower concentration to a region of higher concentration. this process, shown in figure 5.1, uses transport proteins powered by chemi- cal energy.