lecture 6 notes

What are excitable cells modeled as in Lecture 6?

Excitable cells are modeled as electric circuits.

What factors affect electrotonic spread in axons?

The distance that electrotonic spread travels depends on the magnitude of internal resistance in relation to transmembrane resistance.

How does increasing the axon diameter affect action potential (AP) conduction?

Increasing the axon diameter allows for more ions, resulting in lower resistance and faster conduction.

What is the effect of myelin on axon conduction?

Myelin increases transmembrane resistance and acts as insulation, which reduces current leakage and allows for more efficient AP flow.

How does conduction occur in myelinated axons?

Conduction in myelinated axons is described as saltatory, where the AP jumps from node to node.

What is the structure of a myelinated axon?

Internodes are myelinated, while nodes are unmyelinated.

What is found at the node of an axon?

A high density of ion channels is found at the nodes, while there are few under the myelin.

What roles do transmitters and receptors play at synaptic partners?

Transmitters and their receptors can be either excitatory or inhibitory but are not action potentials