Neurotransmitter in Biological Definition

Neuron

... chemically mediated by rapid secretion of neurotransmitter molecules . Pre-synaptic neurons (i.e.the ... at the tip of an axon triggers the release of neurotransmitter at a synaptic gap . Neurotransmitters can ... will only be triggered in the target cell if neurotransmitter molecules acting on their post-synaptic ...

Neurotransmitter

... neuron . A chemical is classified as a neurotransmitter if it respects the following conditions: It ... of action Within the cells , small-molecule neurotransmitter molecules are packaged in vesicles . When an ... ion channels that open or close through neurotransmitter binding. Metabotropic receptor effects on ion ...

Synapse

... part of a cell. The parts of synapses where neurotransmitter is released are called the active zones . At ... across chemical synapses The release of neurotransmitter is triggered by the arrival of a nerve impulse ... nerve terminal, vesicles containing neurotransmitter sit "docked" and ready at the synaptic membrane. ...

Ion channel

... of nerve and muscle, and the voltage-gated calcium channels that control neurotransmitter release in pre-synaptic endings . Ligand-gated channels open in ... the "nicotinic" Acetylcholine receptor , AMPA receptor and other neurotransmitter -gated channels. Cyclic nucleotide-gated channels , ...

Signal transduction

... transduction is the signal amplification . The binding of one or a few neurotransmitter molecules can enable the entry of millions of ions. The binding of one or ... in a multitude of processes, among them muscle contraction, release of neurotransmitter from nerve endings, vision in retina cells, proliferation , ...

Diffusion

... topics List of physics topics Mass transfer Materials science Mechanical ventilation NaKATPase Nervous system neurotransmitter Nitric oxide Nobel Prize in Physiology or Medicine Osmosis Osmotic Quorum sensing Respiration Reverse osmosis ...

Enzyme

... acid to tetrahydrofolic acid DNA gyrase : catalyzes the negative supercoiling of prokaryotic DNA Glutamate decarboxylase : synthesizes the neurotransmitter GABA in the brain Glutathione peroxidase : protects cells by converting hydrogen peroxide to water Isomerase : all those enzymes which ...

Muscle

... by the nerves , the motor nerves and motoneurons in particular. All skeletal muscle and many smooth muscle contractions are facilitated by the neurotransmitter acetylcholine . Muscles and muscular activity account for most of the body's energy consumption. Muscles store energy for their own use in the ...

Nervous system

... the nervous system occurs by two primary mechanisms: Within neuronal nerve fibers by way of action potentials Between neurons by way of neurotransmitter diffusion across synapses . Vertebrate nervous systems The nervous systems of vertebrate animals are often divided into a central ...

Receptor

... stimuli, produces an informative nerve impulse . In biochemistry , a receptor is a protein molecule that receives and responds to a specific neurotransmitter , hormone , or other substance. In immunology , a receptor is the region of an antibody which shows recognition of an antigen . ...

Selective serotonin reuptake inhibitor

... Selective serotonin reuptake inhibitors ( SSRIs ) are a class of antidepressants . They act within the brain to increase the amount of the neurotransmitter , serotonin (5-hydroxytryptamine or 5-HT), in the synaptic gap by inhibiting its reuptake . One notable characteristic of SSRIs is that, unlike ...

Transmembrane receptor

... "loops" sticking out of the membrane. By definition. a receptor's main function is to recognize and respond to a specific ligand, for example, a neurotransmitter or hormone (although certain receptors respond also to changes in transmembrane potential ), and in many receptors these ligands bind to the ...