Hich definition is the best for “semipermeable membrane”?

It is a barrier that prevents materials from moving from one side to the other.

It is a barrier that allows materials to move freely from one side to the other.

It is a barrier with tiny openings that let some, but not all, materials pass through.

It is a barrier that helps materials move from one side to the other.

C

Explanation:

in a semi-permeable membrane, very specific amounts of materials are allowed through. This is particularly helpful in the human body because the body can then create "charge differences" between ions. In these charge differences, neurons can fire and pretty much all movement in your body is achieved because of these membranes. They are also called selective membranes

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