Answer:
To respond to a chemical signal, a cell must have a receptor to which the signaling molecule can bind. Receptors are proteins that are embedded in the cell membrane or located within the cell. They have a specific shape that allows them to bind to specific signaling molecules, such as hormones or neurotransmitters. When a signaling molecule binds to its receptor, it triggers a response within the cell, such as a change in the activity of certain enzymes or the expression of specific genes. This process is known as signal transduction and is an important way that cells can communicate and respond to their environment.
Step-by-step explanation: