Action Potentials and Neurotransmission

These flashcards cover essential concepts related to action potentials, neurotransmission, and the roles of various receptors and neurotransmitters.

What does an action potential jump from one node of Ranvier to the next allow for?

It allows for faster transmission of signals along the axon.

What are the nodes of Ranvier?

They are gaps in the myelin sheath of an axon that facilitate the rapid conduction of action potentials.

What directly influences the postsynaptic cell during neurotransmission?

Ions that flow from the presynaptic cell into the postsynaptic cell.

What is the role of neurotransmitters?

They transmit signals across the synaptic cleft between neurons.

What are ligand-gated ion channels?

They are receptors that open to allow ions to flow through when bound by a neurotransmitter.

What are the two major classes of postsynaptic neurotransmitter receptors?

Ligand-gated ion channels and receptors that use secondary messenger systems.

What are excitatory receptors responsible for?

They move the postsynaptic cell towards depolarization.

What effect do inhibitory receptors have on the postsynaptic cell?

They hyperpolarize the cell, making it more negative.

What must a substance do to qualify as a neurotransmitter?

It must elicit an appropriate response when introduced into the synaptic cleft.

What is the relationship between acetylcholine and muscle cells?

Acetylcholine is the key neurotransmitter that transmits signals from nerve cells to muscle cells.

What is the primary precursor for catecholamines?

The amino acid tyrosine.

How do voltage-gated calcium channels affect neurotransmitter release?

They facilitate the exocytosis of neurotransmitters from the presynaptic neuron.

What is the difference between degradation and reuptake of neurotransmitters?

Degradation involves breaking down the neurotransmitter, while reuptake involves taking the neurotransmitter back into the presynaptic neuron.

What are agonists and antagonists in the context of neurotransmitters?

Agonists enhance neurotransmitter activity, while antagonists block it.

What is the significance of synaptic cleft distance in neurotransmission?

The synaptic cleft separates the presynaptic and postsynaptic membranes, preventing direct cytoplasmic communication.