Final answer:
The term used to describe the cell membrane's ability to allow some substances through while blocking others is selective permeability.
Step-by-step explanation:
The term used to describe the cell membrane's ability to allow some substances through while blocking others is selective permeability. The cell membrane is selectively permeable because it has specific transport proteins and channels that control the movement of substances in and out of the cell. These proteins and channels can recognize and interact with certain molecules, allowing them to pass through the membrane while blocking others.
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