Examples of freewheeling in a Sentence. 1  She led a freewheeling life in the city. 2  James Bond has long been the model of the freewheeling hero who encounters danger and excitement in every corner of the globe.
Myelin Function. By Sally Robertson, BSc. The myelin sheath is a protective covering that surrounds fibres called axons, the long thin projections that extend from the main body of a nerve cell or neuron. This sheath is composed of protein and lipids.he main function of myelin is to protect and insulate these axons and enhance their transmission of electrical impulses. If myelin is damaged, the transmission of these impulses is slowed down, which is seen in severe neurological conditions such as multiple sclerosis.
myelin sheath: conduction of action potential. View full-size image Conduction of the action potential In a myelinated axon (top), the myelin sheath prevents the local current (small black arrows) from flowing across the membrane.This forces the current to travel down the nerve fiber to the unmyelinated nodes of Ranvier, which have a high concentration of ion channels.earch Tips. View full-size image Conduction of the action potential In a myelinated axon (top), the myelin sheath prevents the local current (small black arrows) from flowing across the membrane.