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receptor
receptor A receptor is a protein on a cell’s surface or inside the cell that attaches to a specific signaling substance, such as a hormone, antigen, or neurotransmitter.
A receptor is a protein on a cell’s surface or inside the cell that attaches to a specific signaling substance, such as a hormone, antigen, or neurotransmitter. This binding changes the receptor’s shape and activity, which then affects other molecules and alters cell functioning through signaling pathways.