SDL-1 Synaptic Transmission I & II Flashcards
Axodendritic synapses typically convey (inhibitory/excitatory) signals.
Excitatory
Axosomatic synapses typically convey (inhibitory/excitatory) signals.
Inhibitory
Axoaxonic synapses typically convey signals for (presynaptic/postsynaptic) inhibition.
Presynaptic inhibition.
Modulates neurotransmitter release
Synaptic vesicles carrying neurotransmitter congregate in the ___________ before release into the synaptic cleft.
Presynaptic density
Neurotransmitter receptors congregate in the ______________ following release of neurotransmitter into the synaptic cleft.
Postsynaptic density
What are three important attributes of electrical synapses when compared to chemical synapses?
I. Electrical synapses use gap junctions
II. Electrical synapses make use of bidirectional communication
III. Electrical synapses are faster than chemical synapses
What are three important attributes of chemical synapses when compared to electrical synapses?
I. Chemical synapses use a chemical synapse. Neurotransmitter is released into cleft and then taken up by the postsynaptic cell
II. Chemical synapses use unidirectional communication
III. Chemical synapses are slower than electrical synapses
A chemical needs to meet what four criteria to be considered a neurotransmitter?
I. Localization: It is present at the synapse.
II. Release: It is released following an action potential at a nerve terminal.
III. Mimicry: Structure should be able to elicit same response in a post-synaptic cell in a laboratory setting if reproduced artificially.
IV. Inactivation: Chemical should be inactivated by a specific mechanism.
Relatively small neurotransmitter molecules such as acetylcholine and norepinephrine are made in the (soma/nerve terminal).
Nerve terminal
Peptide neurotransmitters such as opioid peptides are made in the (soma/nerve terminal).
Soma
(T/F) Peptide neurotransmitters are first made in the soma, then transported to the nerve terminal for use.
True
What are two ways the body increases neurotransmitter assembly by enzymes?
I. Increased synthesis of enzyme molecules responsible for neurotransmitter assembly.
II. Phosphorylation of enzymes molecules used in assembly.
(Phosphorylation of enzymes/Increased synthesis of enzymes) is a faster method of increasing production of neurotransmitters.
Phosphorylation of enzymes
What is the purpose of an autoreceptor on a presynaptic cell?
Released neurotransmitter may bind to its corresponding autoreceptor on the presynaptic cell, modulating release and uptake of the neurotransmitter. This allows the body to maintain control in how much neurotransmitter is present at a synapse.
In what four ways is the action of a neurotransmitter terminated?
I. Extracellular degradative enzymes
II. Specific reuptake proteins
III. Diffusion of neurotransmitter away from synapse
IV. Internalization of ligand-receptor complex
A(n) (ionotropic/metabotropic) receptor is a ligand-gated receptor that acts as an ion channel into the cell upon activation.
Ionotropic
A(n) (ionotropic/metabotropic) receptor is a G protein-coupled receptor that elicits its response through secondary mediators upon activation.
Metabotropic
Nicotinic receptors tend to be (ionotropic/metabotropic).
Ionotropic
Muscarinic receptors tend to be (ionotropic/metabotropic).
Metabotropic
(Ionotropic/Metabotropic) receptors tend to elicit their responses faster.
Ionotropic
(Ionotropic/Metabotropic) receptors have a longer duration.
Metabotropic
(T/F) Excitation and inhibition are largely dependent on the neurotransmitter released at the synapse.
False. It is the RECEPTOR that accounts for the difference, never the neurotransmitter.
Excitation consists of (hyperpolarization/depolarization) of the membrane potential.
Depolarization
Inhibition consists of (depolarization/hyperpolarization) of the membrane potential.
Hyperpolarization
Too much repeated excitation or too little inhibition of a receptor may result in a condition known as _____________.
Epilepsy
Too little excitation or too much inhibition of a receptor may result in ____________ or ___________.
Anesthesia; coma
What are the four general groups used to classify neurotransmitters?
I. Amines (Acetylcholine, Dopamine, Norepinephrine)
II. Amino Acids (Glutamate, GABA, Glycine)
III. Neuropeptides (Opioids)
IV. Gases (Nitric Oxide)
In what ways are peptide neurotransmitters different when compared to classical neurotransmitters such as acetylcholine?
I. Peptide neurotransmitter synthesis is directed by mRNA
II. Peptide neurotransmitters usually exist as an inactive precursor first
III. Peptide NTs are made in the soma and transported to the nerve terminal (vs. being synthesized at the nerve terminal)
IV. Peptide NTs become activated during transport by peptidases that cleave them
Acetylcholine acts on what receptors in the body?
I. Nicotinic
II. Muscarinic
Dopamine acts on what receptors in the body?
I. D1
II. D2