How Do Myelin Sheaths Increase the Speed with Which Action

question 13

Multiple Choice

How do myelin sheaths increase the speed with which action potentials are propagated along an axon?

• A)They increase the permeability of Na⁺ ions in the plasma membrane.
• B)They amplify the action potential by increasing sodium influx along the entire distance of the neuron.
• C)They cause action potentials to "jump" down the axon rather than travel in a continuous path along every site on the axon.
• D)All of the above answers apply.

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Definitions:

Portfolio Variance

A measure of the dispersion of returns of a portfolio, indicating the level of investment risk.

Cyclical Stock

Shares of companies whose earnings are heavily influenced by economic cycles, often rising during expansions and falling during recessions.

Countercyclical Stock

A stock of a company whose performance is inversely related to the economy's overall performance; it tends to do well during economic downturns.

Security Market Line

A line that represents the relationship between risk and expected return of the market in the Capital Asset Pricing Model (CAPM).