What characteristic does a semipermeable membrane exhibit?

A semipermeable membrane is defined by its ability to selectively allow certain substances to pass through while preventing others from doing so. This selective permeability is crucial in biological and physiological processes, as it helps maintain the internal environment of cells and organs, allowing them to regulate the movement of essential nutrients and waste products.

For instance, in biological systems, semipermeable membranes such as cell membranes enable water, ions, and small molecules to enter or exit the cell, while larger molecules or charged particles may be restricted. This property is vital for processes like osmosis and diffusion, which are essential for maintaining homeostasis in living organisms.

In contrast to the choices that describe full permeability or complete impermeability, the defining characteristic of semipermeability lies in its selective nature, which ensures that only specific substances can pass through while others remain blocked. This selectivity is fundamental for the effective functioning of cells and their interactions with their environment.