Answer with Explanation:
A "screen" is semipermeable just like the cell membrane because it only allows certain tiny things to pass through. For example, an aircon protector filter screen allows the air to be ventilated into a room but not the contaminants coming from outside. These contaminants may include dirt, pollens, smoke, dust, etc. In a similar nature, the cell membrane only allows small particles to pass through just like oxygen.
Both the screen and the cell membrane act as barriers. Only certain things can diffuse readily through them while the other things are being trapped.