Receptor potential
Encyclopedia
Receptor potential, a type of graded potential, is the transmembrane potential difference of a sensory receptor
.
A receptor potential is often produced by sensory transduction. It is generally a depolarizing
event resulting from inward current flow. The influx of current will often bring the membrane potential
of the sensory receptor towards the threshold for triggering an action potential
.
A receptor potential is a form of graded potential. An example of this is in a taste bud
, where taste is converted into an electrical signal sent to the brain. When stimulated the taste bud triggers the release of neurotransmitter through exocytosis
of synaptic vesicles from the presynaptic membrane. The neurotransmitter molecules diffuse across the synaptic cleft to the postsynaptic membrane.
Graded potentials vary in size. They arise from the summation of the individual actions of ligand-gated ion channel
proteins, and decrease over time and space. They are distinct from voltage-gated sodium and potassium channels
.
Sensory receptor
In a sensory system, a sensory receptor is a sensory nerve ending that responds to a stimulus in the internal or external environment of an organism...
.
A receptor potential is often produced by sensory transduction. It is generally a depolarizing
Depolarization
In biology, depolarization is a change in a cell's membrane potential, making it more positive, or less negative. In neurons and some other cells, a large enough depolarization may result in an action potential...
event resulting from inward current flow. The influx of current will often bring the membrane potential
Membrane potential
Membrane potential is the difference in electrical potential between the interior and exterior of a biological cell. All animal cells are surrounded by a plasma membrane composed of a lipid bilayer with a variety of types of proteins embedded in it...
of the sensory receptor towards the threshold for triggering an action potential
Action potential
In physiology, an action potential is a short-lasting event in which the electrical membrane potential of a cell rapidly rises and falls, following a consistent trajectory. Action potentials occur in several types of animal cells, called excitable cells, which include neurons, muscle cells, and...
.
A receptor potential is a form of graded potential. An example of this is in a taste bud
Taste bud
Taste buds contain the receptors for taste. They are located around the small structures on the upper surface of the tongue, soft palate, upper esophagus and epiglottis, which are called papillae. These structures are involved in detecting the five elements of taste perception: salty, sour,...
, where taste is converted into an electrical signal sent to the brain. When stimulated the taste bud triggers the release of neurotransmitter through exocytosis
Exocytosis
Exocytosis , also known as 'The peni-cytosis', is the durable process by which a cell directs the contents of secretory vesicles out of the cell membrane...
of synaptic vesicles from the presynaptic membrane. The neurotransmitter molecules diffuse across the synaptic cleft to the postsynaptic membrane.
Graded potentials vary in size. They arise from the summation of the individual actions of ligand-gated ion channel
Ligand-gated ion channel
Ligand-gated ion channels are one type of ionotropic receptor or channel-linked receptor. They are a group of transmembrane ion channels that are opened or closed in response to the binding of a chemical messenger , such as a neurotransmitter.The binding site of endogenous ligands on LGICs...
proteins, and decrease over time and space. They are distinct from voltage-gated sodium and potassium channels
Voltage-gated ion channel
Voltage-gated ion channels are a class of transmembrane ion channels that are activated by changes in electrical potential difference near the channel; these types of ion channels are especially critical in neurons, but are common in many types of cells....
.