On the other hand a nerve cord is a solid strand of nervous tissue, forming part of central nervous system, especially of invertebrates. The main difference between the two is that notochord is a part of skeleton system whereas nerve cord is a part of nervous system.Source(s): Shewta · 2 years ago. Thumbs up. 2.n the other hand a nerve cord is a solid strand of nervous tissue, forming part of central nervous system, especially of invertebrates. The main difference between the two is that notochord is a part of skeleton system whereas nerve cord is a part of nervous system. Source(s):