Question

What is the function of transport molecules

Answer 1

they assist with the transport, or movement, of molecular substances across the semi-permeable cytoplasmic bi-lipid cellular membrane; substances that would otherwise be unable to pass through. A special example is that of the nerve-cell's sodium|potassium pumps / ion channels [or gates] that after allowing a nerve impulse to pass must re-activate those gates to replenish the ion supplies for the next pass.
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