Question

Cells grown in the laboratory are mixed with a dye molecule that is unable to pass through the plasma membrane. If a ligand is added to the cells, the dye is then observed entering the cells. Interpreting this result, what type of receptor did the ligand bind to on the cell surface?

a) G protein-coupled receptor
b) Intracellular receptor
c) Ion channel receptor
d) Cell-surface receptor

Answer 1

The ligand most likely binds to a cell-surface receptor on the cell surface.

Step-by-step explanation:

The ligand most likely binds to a cell-surface receptor on the cell surface. Cell-surface receptors are responsible for transmitting signals from outside the cell to the cytoplasm. They bind to hydrophilic ligands that are unable to pass through the plasma membrane, like the dye molecule in this experiment. When the ligand binds to the cell-surface receptor, a signaling pathway is initiated, allowing the dye to enter the cell.