(hope this helps can I pls have brainlist (crown) ☺️)
Explanation:
Barriers and gatekeepers are both functions of cell membranes. They're semi-permeable, which means some molecules can pass through but others can't. The concentration of particular chemicals inside the cell is controlled by specialised proteins in the cell membrane.
A cell's plasma membrane, also known as the cell membrane, offers protection. It also maintains a constant environment within the cell, and the membrane serves a variety of purposes. The first is to carry nutrients into the cell, and the second is to transport harmful chemicals out.
The role of a cell membrane is to serve as barriers & gatekeepers. Special proteins in the cell will regulate the concentration of specific molecules inside the cell.