Neuroscience: Synaptic Transmission Quiz

Calcium ions (Ca++) are crucial for triggering exocytosis, the process of releasing neurotransmitters from the presynaptic terminal.

The amount of calcium ions (Ca++) entering the presynaptic terminal determines the strength of the signal.

A protein complex that helps fuse synaptic vesicles (containing neurotransmitters) with the presynaptic membrane.

The process where the presynaptic terminal releases neurotransmitters into the synaptic cleft.

Neurotransmitter release is regulated by various proteins, including calcium channels, calcium-binding proteins, and membrane fusion proteins.

A graded potential that occurs in the post-synaptic neuron due to the release of a single vesicle of neurotransmitter.

The influx of calcium ions into the presynaptic terminal, triggered by the arrival of an action potential. This influx is crucial for the release of neurotransmitter.

A type of calcium channel that is sensitive to changes in membrane voltage. These channels open in response to depolarization of the presynaptic terminal, allowing calcium to flow into the cell, which triggers neurotransmitter release.

The hypothesis that each mEPP is caused by the release of a single synaptic vesicle containing neurotransmitter.

A type of synapse where communication between neurons occurs via chemical messengers called neurotransmitters. These messengers are released from the presynaptic neuron and bind to receptors on the postsynaptic neuron, triggering a signal.

A type of synapse where communication between neurons occurs directly through electrical signals that flow through specialized channels connecting the two cells.

The space between the presynaptic and postsynaptic neurons at a chemical synapse. Neurotransmitters travel across this gap to reach the postsynaptic neuron.

Specialized proteins located on the postsynaptic membrane of a neuron. They bind to neurotransmitters, triggering a signal in the postsynaptic neuron.

A type of receptor that directly alters the ion permeability of the postsynaptic membrane. These receptors are directly gated by neurotransmitters and commonly involved in fast synaptic transmission.

A type of microscopy that uses a beam of electrons to create images of very small structures. Highly detailed images of cells and organelles can be observed.

A type of microscopy that uses a beam of electrons to scan the surface of a specimen, producing three-dimensional images. It provides detailed information about the surface structure.

A type of receptor that directly opens an ion channel when a neurotransmitter binds to it. This allows ions to flow across the cell membrane, changing the membrane potential and triggering a rapid signal.

A type of postsynaptic potential that makes the neuron more likely to fire an action potential. It's caused by an influx of positive ions, like sodium, into the neuron.

A type of postsynaptic potential that makes the neuron less likely to fire an action potential. It's caused by an influx of negative ions, like chloride, or by an efflux of positive ions, like potassium, from the neuron.

The primary neurotransmitter responsible for muscle contraction and many other functions. It binds to nicotinic acetylcholine receptors to elicit its effects.

The enzyme that breaks down acetylcholine in the synaptic cleft, terminating its signaling.

A major excitatory neurotransmitter in the CNS. It acts on AMPA, kainate, and NMDA receptors.

The main inhibitory neurotransmitter in the CNS. It binds to GABA receptors, which are coupled to chloride channels, causing hyperpolarization.

A neurotransmitter that works similarly to GABA in the CNS, causing inhibition.

These channels increase membrane permeability to chloride ions (Cl-), leading to a hyperpolarizing effect by making the membrane potential more negative.

These neurotransmitters, like GABA and glycine, bind to ionotropic receptors, opening Cl- channels and producing an inhibitory effect. This makes the postsynaptic cell less likely to fire an action potential.

They counter the effects of excitatory postsynaptic potentials (EPSPs). This can lead to a reduction in the probability of the postsynaptic neuron firing.

By increasing membrane conductance to Cl-, these neurotransmitters effectively "short-circuit" the flow of excitatory current. This is like creating a path for current to flow out instead of towards the axon, preventing an action potential.

They are short proteins synthesized in the cell body and transported to the axon terminal. They can act as neurotransmitters for rapid signaling or as modulators for slower effects.