AP BIOLOGY

Detailed explanation-1: -A ligand is a molecule that binds another specific molecule, in some cases, delivering a signal in the process. Ligands can thus be thought of as signaling molecules. Ligands interact with proteins in target cells, which are cells that are affected by chemical signals; these proteins are also called receptors.

Detailed explanation-2: -The ligand is a chemical messenger released by one cell to signal either itself or a different cell. The binding results in a cellular effect, which manifests as any number of changes in that cell, including altering gene transcription or translation or changing cell morphology.

Detailed explanation-3: -Signaling molecules are often called ligands, a general term for molecules that bind specifically to other molecules (such as receptors). The message carried by a ligand is often relayed through a chain of chemical messengers inside the cell.

Detailed explanation-4: -Neurons, or nerve cells, have ligand-gated channels that are bound by neurotransmitters. Diagram of a ligand-gated ion channel. When the ligand binds to a closed ion channel in the plasma membrane, the ion channel opens and ions can pass through it, moving into or out of the cell (down their concentration gradient).

Detailed explanation-5: -Cells have proteins called receptors that bind to signaling molecules and initiate a physiological response. Different receptors are specific for different molecules.