Final answer:
Conduction along a nerve is increased by the myelination of axons, which enables faster saltatory conduction, and by the axon's diameter, where a larger diameter leads to less resistance and quicker ion flow. Myelin sheaths also conserve energy in the transmission of signals, and this efficiency can be measured with an ECG.
Step-by-step explanation:
Nerve Conduction and Myelination
The mechanisms that increase conduction along a nerve include the myelination of axons and the diameter of the axons themselves. Myelinated axons exhibit saltatory conduction, where the action potential jumps from one node of Ranvier to the next, significantly increasing conduction speed compared to continuous conduction in unmyelinated axons. The larger diameter of an axon can also increase conduction speed due to less resistance, allowing for faster movement of Na+ ions, akin to water flowing more quickly through a wide river rather than a narrow creek. In demyelinating diseases such as multiple sclerosis, the loss of myelin sheaths causes current to leak from the axon, resulting in slower action potential conduction and impeded nerve signal transmission.
Myelin sheaths not only enhance the speed of nerve conduction but also reduce the energy required for signal transmission. In turn, the increased efficiency of action potentials in the heart, for example, can be observed and measured using an electrocardiogram (ECG).