A molecule that is not membrane permeable binds to a membrane protein on the outside of a cell. This changes the conformation of the protein, causing the binding site to face the inside of the cell. The molecule is then released into the cell and the conformation of the binding site changes again so that it is outside the cell. This is a description of what type of transport(er)?

MCQs on the cell and its structures, including molecular compounds, structural features, and organelles including the nucleus, cytoskeleton, and extracellular matrix. Particular emphasis on transport mechanisms and membrane trafficking, cellular signaling, the cell cycle including mitosis and meiosis, and gene expression.