Difference Between Notochord and Vertebral Column

The key difference between notochord and vertebral column is that notochord is a flexible rod-like structure that supports the nervous tissue in lower chordates, while the vertebral column is a structure containing 33 vertebrae, running from the skull up to the pelvis in vertebrate higher chordate animals.

Both notochord and vertebral column are features of chordates. These two structures extend from the head up to the tail in the dorsal region of the bod. Moreover, both take part in different functions and play key roles in the body. Thus, this article highlights the difference between notochord and vertebral column.

CONTENTS

1. Overview and Key Difference
2. What is Notochord 
3. What is Vertebral Column
4. Similarities Between Notochord and Vertebral Column
5. Side by Side Comparison – Notochord vs Vertebral Column in Tabular Form
6. Summary

What is Notochord?

The notochord is a flexible rod-like structure that is derived from the mesoderm (mesodermal cells), which is considered as the principal structural element that supports the body of lower chordates. It is a cartilaginous structure. The notochord also plays an important role in the organization of the development of the nervous system.

In the context of vertebrates, the notochord occurs during early embryonic stages. In adult vertebrates, the notochord develops as a part of the vertebral column that organizes into a structure which surrounds the nerve cord. Notochord typically extends the whole length of the head to tail.

The development of the notochord takes place as follows. During gastrulation, the notochord is derived parallel to the development of the neural plate. The mesodermic cells then become condensed and rigid to form the notochord.

What is Vertebral Column?

The vertebral column is a structure containing 33 vertebrae (individual bones) that extends from the skull up to the pelvis. The vertebral column contains four main regions of vertebrae: cervical vertebrae, atlas vertebrae, axis vertebrae and thoracic vertebrae. Furthermore, the main function of the vertebral column is to provide protection to the spinal cord, nerve roots and many internal organs.

Furthermore, it provides a base for attachment of ligaments, muscles and tendons. The vertebral column also provides structural support to the head and shoulders and connects the lower body with the upper body. Moreover, it plays a major role during weight distribution and body balance.

What are the Similarities Between Notochord and Vertebral Column?

• Both structures are present in chordates.
• They provide sites for attachment of different components of the body, including muscles.
• Also, both extend from the head up to the tail in the dorsal region of the body.
• Moreover, both provide structural support.

What is the Difference Between Notochord and Vertebral Column?

The key difference between notochord and vertebral column is that notochord is a flexible rod-like structure that supports the nervous tissue in lower chordates, while the vertebral column is a structure containing 33 vertebrae, running from the skull up to the pelvis in vertebrate higher chordate animals. Also, another significant difference between notochord and vertebral column is their composition; notochord is made up of cartilage, while the vertebral column is made up of bones.

Below infographic shows more details regarding the difference between notochord and vertebral column.

Summary – Notochord vs Vertebral Column

In summary, the notochord and vertebral column are present in chordates. The notochord occurs in lower chordates. Moreover, this structure provides structural support and base for attachment. The vertebral column is a structure made up of 33 vertebrae that run from the skull up to the pelvis in vertebrate higher chordate animals. The vertebral column consists of four distinct regions: cervical vertebrae, atlas vertebrae, axis vertebrae and thoracic vertebrae. Thus, this is the difference between notochord and vertebral column.

Reference:

1. “Notochord.” Encyclopædia Britannica, Encyclopædia Britannica, Inc., 2 Nov. 2016, Available here.
2. “The Vertebral Column.” TeachMeAnatomy, 28 Mar. 2018, Available here.

Image Courtesy:

1. “Gray19 with color” By Derivative of Image:Gray19.png by (presumably) User:The cat – Image:Gray19.png (Public Domain) via Commons Wikimedia
2. “Figure 38 01 07” By CNX OpenStax – (CC BY 4.0) via Commons Wikimedia