Fundamental principles of the brain Flashcards
Synaptic Transmission and The Nervous System
What is synaptic transmission?
The process by which neurons communicate with each other by transmitting signals across a synapse.
What is an electrical synapse?
A type of synapse where electrical signals pass directly between neurons through gap junctions, allowing for fast communication.
What is a chemical synapse?
A type of synapse where neurotransmitters are released from the presynaptic neuron to communicate with the postsynaptic neuron.
What is a neuromuscular junction?
The synapse between a motor neuron and a muscle fiber, responsible for muscle contraction.
What is a motor end-plate?
The specialized area of the muscle fiber membrane that receives signals from the motor neuron.
What is glutamate (Glu)?
The most common excitatory neurotransmitter in the brain.
What is gamma-aminobutyric acid (GABA)?
The primary inhibitory neurotransmitter in the brain.
What is glycine (Gly)?
An inhibitory neurotransmitter primarily found in the spinal cord and brainstem.
What is acetylcholine (ACh)?
A neurotransmitter involved in muscle activation, autonomic functions, and cognition.
What are transporters?
Proteins that help move neurotransmitters across cell membranes, often for reuptake or storage.
What is a voltage-gated calcium channel?
A channel that opens in response to membrane depolarization, allowing calcium to enter the neuron and trigger neurotransmitter release.
What is an excitatory postsynaptic potential (EPSP)?
A depolarization of the postsynaptic membrane that increases the likelihood of an action potential.
What is an inhibitory postsynaptic potential (IPSP)?
A hyperpolarization of the postsynaptic membrane that decreases the likelihood of an action potential.
What are G-proteins?
Intracellular proteins that relay signals from receptors to other cellular processes.
What are second messengers?
Molecules that transmit signals inside cells in response to receptor activation.
What are inhibitors?
Molecules that prevent or reduce the activity of enzymes, receptors, or other biological processes.
What are receptor antagonists?
Molecules that bind to receptors and block their activation.
What are receptor agonists?
Molecules that bind to receptors and mimic the effect of natural neurotransmitters.
What is shunting inhibition?
A form of inhibition that reduces excitatory signal transmission by increasing membrane conductance.
What is modulation?
The process by which neurotransmitters alter neuronal function through changes in receptor or ion channel activity.
What is a gap junction?
A specialized intercellular connection that allows ions and small molecules to pass directly between adjacent cells, facilitating electrical synapses.
What is spatial summation?
The addition of EPSPs from multiple synapses occurring at different locations on the neuron.
What is temporal summation?
The addition of EPSPs from repeated activation of a single synapse over time.
What are autoreceptors?
Presynaptic receptors that regulate neurotransmitter release, often through negative feedback.
