The property of cell membranes that allows them to precisely determine what substances can enter or leave a cell is called

Cell membrane is a part of  a cell that consists of a lipid bilayer with embedded protein layer. It protects the cell from the surroundings and also regulate the entry of material in and out of the cell. The cell membrane is semipermeable (selective permeability) a property that helps it to control the materials entering or leaving the cell. 

Explanation:

Kelp forests are the anchor of nearshore ocean wildlife communities across the U.S. West Coast and northeast, sustaining marine biodiversity by providing shelter, habitat and even food for an array of fish and invertebrates.