Cells in a large multicellular organism communicate with each other by chemical signals. these signals are passed from one cell to another. to receive and respond to a chemical signal, a cell must have a for that chemical.

The cell to cell communication is performed by certain chemical signals in the multi-cellular organisms. The chemical signal is perceived by the cell with the help of receptor. The signalling molecule binds to receptor thereby generating a response. The signalling molecule can only bind to a specific receptor. For example, nerve growth factor can only bind with nerve growth receptors and insulin binds only with insulin receptor.  

Thus, To receive and respond to a chemical signal, a cell must have a receptor for that chemical.

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Cell to cell signalling

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