What is the function of the myelin sheath?

The main function of myelin sheeth is that:

1. It acts an electrical insulator for neuron and prevent electrical impulses travelling through sheeth.

2. The sheeth prevents the movement of ion into or out of neuron OR it prevents depolarization.

Explanation:

oceans

indian ocean

pacific ocean

atlantic ocean

arctic ocean

southern ocean

i think a) betsy can donate only blood to mark is correct because, mark and betsy have the same blood type. whereas nobody else has b+ blood so betsy can't donate to them.