Cell signaling is the complex process by which cells perceive and respond to their environment. It is essential for homeostasis, growth, and immune responses.
A signaling molecule (ligand) binds to a specific receptor on the cell surface or inside the cell. signaling
The signal finally triggers a specific cellular activity, such as gene expression or enzyme activation. Types of Signaling: Autocrine: A cell targets itself. Cell signaling is the complex process by which
Long-distance signaling via the bloodstream (e.g., hormones). often called a signaling cascade (e.g.
Signaling between cells in physical contact.
Nearby cells are targeted (e.g., neurotransmitters).
The receptor triggers a relay of intracellular molecules, often called a signaling cascade (e.g., using G-proteins or kinases).