AP BIOLOGY

Detailed explanation-1: -The cell membrane is called selectively permeable as it only allows specific molecules to pass. Only specific molecules like water and gaseous molecules can pass through the cell membrane directly. It stops the flow of other molecules towards the two sides.

Detailed explanation-2: -It is true that a membrane which allows only certain substances to pass through, but does not allow others to pass through it is called a selectively permeable membrane. For example, the plasma membrane of eukaryotic cells.

Detailed explanation-3: -selectively permeable: the characteristic of a membrane that allows some substances through but not others. solute: a substance dissolved in another to form a solution.

Detailed explanation-4: -A membrane which allows certain substances to pass through it, but not others is called a selectively permeable membrane.

Detailed explanation-5: -Cell membranes serve as barriers and gatekeepers. They are semi-permeable, which means that some molecules can diffuse across the lipid bilayer but others cannot.