Chapter 33.1, Problem 5MI

Summary Introduction

To analyze:

The myelin sheath increases the speed at which impulses move.

Introduction:

The basic working unit found in the brain is the neuron. Neuron is the specialized cell that helps in the transmission of sensory information. These cells transport information to muscle, nerve cells, and glands.

Explanation of Solution

Myelin sheath is the insulting cover on the axon. It helps in the fast transmission of electrical impulses across the neuron. Neurons containing myelin sheath conducts electrical impulse at a much faster rate as compared to non-myelinated neuron. Nodes of ranvier are the non-myelinated portions of axon that are located between myelinated areas. As, myelin sheath acts as an insulator, part of axon covered with this sheath does not conduct electrical impulse. So, in myelinated neuron, actions potentials pass along the nodes of Ranvier only. By this, electrical impulse jump from one node to another, leading to faster transmission of information.