How do chemical messengers transmit information to the cell?

Chemical messengers, such as hormones or neurotransmitters, primarily transmit information to the cell by binding to specific receptor proteins located on the surface of the target cell. This interaction is fundamental to cellular communication and signaling.

When a chemical messenger binds to its receptor, it triggers a conformational change in the receptor, leading to a cascade of intracellular events. This can involve the activation of various signaling pathways, the release of secondary messengers, or changes in gene expression. The specificity of this binding is critical because different receptors respond to different messengers, allowing cells to respond appropriately to a wide variety of signals in their environment.

The other methods of transmission mentioned do not effectively encompass the primary mechanism by which most chemical messengers exert their effects. While some small or nonpolar molecules can diffuse across the membrane, many messengers, especially polar ones, cannot enter the cell directly and rely instead on receptor-mediated pathways to convey their signals accurately and effectively. Forming complexes with DNA is also unrelated to the initial transmission of information by most chemical messengers, as this typically pertains to the downstream effects following receptor activation.