receptor
Quick Summary
A receptor is a molecule, typically a protein, that receives signals for a cell. These signals come from small molecules called ligands, which can be hormones or other signaling molecules. Ligands bind specifically to receptors, initiating a cellular response.123
Receptors can be located on the cell surface or inside the cell. When a ligand binds to a receptor, it can either stimulate the receptor to transmit a signal (agonist) or block the receptor's function (antagonist). This binding and activation process is crucial for how cells interact with their environment and respond to various stimuli, including those from drugs and the body's own chemical messengers. For example, receptors are involved in senses like smell and play a role in how medications affect the body.14
Ask Britannica AI about this topic
Britannica doesn't have a full article on this topic, so we've curated a list of our relevant coverage.
- cell cycle
…four groups—growth factors, growth factor receptors, signal transducers, and nuclear regulatory proteins (transcription factors). For a stimulatory signal to reach the nucleus and “turn on” cell division, four main steps must occur. First, a growth factor must bind to its receptor on the cell membrane. Second, the receptor must become…
Read More…four groups—growth factors, growth factor receptors, signal transducers, and nuclear regulatory proteins (transcription factors). For a stimulatory signal to reach the nucleus and “turn on” cell division, four main steps must occur. First, a growth factor must bind to its receptor on the cell membrane. Second, the receptor must become…
Read More 
chemoreceptionSignal transduction…commonly involves specific proteins called receptors that are embedded in the cell membrane.
Read More…commonly involves specific proteins called receptors that are embedded in the cell membrane.
Read More
cellSignal receptorsThe ability of a cell to respond to an extracellular signal depends on the presence of specific proteins called receptors, which are located on the cell surface or in the cytoplasm. Receptors bind chemical signals that ultimately trigger a mechanism to modify the behavior…
Read MoreThe ability of a cell to respond to an extracellular signal depends on the presence of specific proteins called receptors, which are located on the cell surface or in the cytoplasm. Receptors bind chemical signals that ultimately trigger a mechanism to modify the behavior…
Read More
human endocrine systemTraditional endocrinology…and activating specific molecules called receptors. Receptors are found on the surface of target cells in the case of protein and peptide hormones, or they are found within the cytoplasm or nuclei of target cells in the case of steroid hormones and thyroid hormones. Each receptor has a strong, highly…
Read More…and activating specific molecules called receptors. Receptors are found on the surface of target cells in the case of protein and peptide hormones, or they are found within the cytoplasm or nuclei of target cells in the case of steroid hormones and thyroid hormones. Each receptor has a strong, highly…
Read More
immune systemReceptor moleculesLymphocytes are distinguished from other cells by their capacity to recognize foreign molecules. Recognition is accomplished by means of receptor molecules. A receptor molecule is a special protein whose shape is complementary to a portion of a foreign molecule. This complementarity of shape…
Read MoreLymphocytes are distinguished from other cells by their capacity to recognize foreign molecules. Recognition is accomplished by means of receptor molecules. A receptor molecule is a special protein whose shape is complementary to a portion of a foreign molecule. This complementarity of shape…
Read More
human nervous systemNeurotransmitters and receptorsUpon reaching their target organs by traveling with the blood vessels that supply them, sympathetic fibers terminate as a series of swellings close to the end organ. Because of this anatomical arrangement, autonomic transmission takes place across a junction rather than a synapse. “Presynaptic”…
Read MoreUpon reaching their target organs by traveling with the blood vessels that supply them, sympathetic fibers terminate as a series of swellings close to the end organ. Because of this anatomical arrangement, autonomic transmission takes place across a junction rather than a synapse. “Presynaptic”…
Read More
smokingAddiction…and peripheral nervous system have receptor proteins on their surfaces to which nicotine binds, much in the way that a key fits into a lock. When a molecule of nicotine binds to a nicotine receptor, it causes the neuron to transmit a nerve impulse to various target organs and tissues.…
Read More…and peripheral nervous system have receptor proteins on their surfaces to which nicotine binds, much in the way that a key fits into a lock. When a molecule of nicotine binds to a nicotine receptor, it causes the neuron to transmit a nerve impulse to various target organs and tissues.…
Read More