L11 Synapses and imbalances

What process occurs at Letter A in the axon during action potential?

Resting potential

What is the status of Na+ ion channels at Letter A?

Closed

What is the status of K+ ion channels at Letter A?

Closed

What process occurs at Letter B in the axon?

Depolarisation

What is the status of Na+ ion channels at Letter B?

Open

What is the status of K+ ion channels at Letter B?

Closed

What process occurs at Letter C in the axon?

Repolarisation

What is the status of Na+ ion channels at Letter C?

Open

What is the status of K+ ion channels at Letter C?

Open

What does a stimulus cause in the neurons during action potential propagation?

Depolarisation of the first part of the axon.

What happens after the first part of the axon depolarises?

Depolarisation occurs slightly further along the axon.

What are the two positive ions responsible for changes in electrical potential?

Sodium (Na+) and Potassium (K+) ions.

What does the QRS complex in an ECG represent?

Ventricular Depolarisation.

What causes the release of neurotransmitters at a synapse?

Fusion of vesicles with the presynaptic membrane.

What happens when neurotransmitter binds to receptors on the postsynaptic membrane?

Sodium ion channels open leading to depolarisation.

What drug type mimics neurotransmitters and leads to an increase in action potentials?

Agonist drugs.

What neurotransmitter is linked to muscle contraction at neuromuscular junctions?

Acetylcholine.

How can serotonin levels be increased?

By certain medications or lifestyle changes.

What is L-Dopa used for?

To treat Parkinson’s disease.