Chapter 2 Vocab

Vesicle

tiny nearly spherical packet filled with neurotransmitter molecules

Transporter Protein

special membrane protein that moves the neurotransmitter back into the presynaptic neuron

Synaptic Cleft

space between the presynaptic and postsynaptic neurons

Synapse

specialized gap as a point of communication between two cells

Reflex

automatic muscular response to stimuli

Reflex Arc

circuit from sensory neuron to muscle response

Temporal Summation

cumulative effect of repeated stimuli within a brief time

Presynaptic Neuron

cell that delivers transmission to another cell

Postsynaptic Neuron

cell that receives transmission from another cell

Excitatory Postsynaptic Potential (EPSP)

graded depolarization

Spatial Summation

combination of effects of two or more synapses onto a single cell

Inhibitory Postsynaptic Potential (IPSP)

temporary hyperpolarization of a membrane

Amino Acid

acid containing an amine group (NH2)

Monoamine

chemical formed by a change in certain amino acids

Purine

category of chemicals including adenosine and several of its derivatives

Neurotransmitter

chemical released by neurons that affects other neuron

Nitric Oxide

gas released by many small local neurons

Catecholamine

compounds that contain a catechol and an amine group

MAO (Monoamine Oxidase)

enzyme that converts catecholamines and serotonin into synoptically inactive chemicals

Exocytosis

release of neurotransmitter from the presynaptic neuron into the synaptic cleft

Ionotropic Effect

synaptic result that depends on the rapid opening of some kind of gate in the membrane

Metabotropic Effect

sequence of metabolic reactions that produces slow and long-lasting effects at a synapse

Second Messenger

chemical that, when activated by a neurotransmitter, initiates communication to many areas within the neuron

Neuropeptide

chain of amino acids

Nicotine

stimulant drug that stimulates certain acetylcholine receptors

Acetylcholinesterase

enzyme that breaks down acetylcholine into acetate and choline

COMT

enzyme that breaks down excess dopamine into inactive chemicals that cannot stimulate the dopamine receptors

Amphetamine

drug that blocks reabsorption of dopamine and other neurotransmitters

Methylphenidate

stimulant drug prescribed for ADHD that increases stimulation of dopamine synapses

2-AG (sn-2 arachidonylglycerol)

chemical that binds to cannabinoid receptors

Gap Junction

direct contact of one neuron with another, enabling electrical transmission