Difference Between Spinal Cord and Backbone: Function, Parts, Segments

What is the Spinal Cord?

The spinal cord is the part of the central nervous system that goes along from the brainstem to the vertebral column. It offers a pathway of nerve signals between the brain and the rest of the body in such a way that sensory inputs reach the brain and responses in the form of commands reach muscles and organs.

Structure & Anatomy

• The spinal cord is cylindrical, surrounded and protected by the vertebrae and their layers of the meninges, which are important for protection.

• It highlights the segmented anatomy of the cord formed by the grey matter that houses the cell bodies of the nerve cells and the white matter held by the axons of the nerve cells.

Functions of the Spinal Cord

• The spinal cord also functionally maintains simple and complex reflex actions, for example a patellar reflex.

• While it also mediates autonomic functions, among which bladder control and temperature regulation are excellent examples.

• These give an essential dimension altogether to the spine insofar as the capabilities of functioning of the nervous system are concerned.

What Is the Backbone?

The backbone is also referred to as the vertebral column or spine, constituting therefore a vital part of the skeletal system in the body that serves as a supportive and protective vault to the spinal cord.

Structure & Components

• Anatomically it consists of a sequence of 33 vertebrae aligned in column fashion, categorically termed cervical, thoracic, lumbar, sacral, and coccygeal.

• Every two vertebrae are separated by an intervertebral disc which can function as a "shock absorber".

• A backbone extends from the base of the skull to the pelvis, providing structure, flexibility of movement, and maintenance of upright body position.

Functions of the Backbone

• Functionally, the backbone is responsible for the protection of the spinal cord.

• Supports the weight and movement of the body

• Plays an integral role in the attachment of muscles and ligaments in the body—essentially, a responsible feature in the role of the human skeletal system about the performance of protection and motion is concerned.

Spinal Cord vs Backbone — Key Differences

It is one of the most important differences and comparison articles in biology. The differences are listed below:

Spinal Cord vs Backbone NEET MCQs (With Answers & Explanations)

Important questions asked in NEET from this topic are:

• Anatomy of spinal cord and backbone

• Functions of spinal cord and backbone

• Spinal cord vs Backbone

Practice Questions for NEET

Q1. The spinal cord extends from the foramen magnum at the base of the skull to the L1/L2 vertebra where it terminates as the

1. Conus medullaris (medullary cone)

2. Coccygeal vertebra

3. Epiduramater

4. Choroid plexus

Correct answer: 1) Conus medullaris (medullary cone)

Explanation:

The spinal cord, an essential component of the central nervous system, originates from the foramen magnum, a significant aperture situated at the skull's base, and extends down to the L1/L2 vertebral levels. It does not stretch throughout the vertebral column's entirety, but rather concludes at this point, transforming into the conus medullaris. Following the conus medullaris, the cauda equina, a collection of spinal nerve fibres, descends within the vertebral canal.

Hence, the correct answer is option 1) Conus medullaris (medullary cone).

Q2. The number of pairs of thoracic spinal nerves is

1. 31

2. 12

3. 5

4. 8

Correct answer: 2) 12

Explanation:

There are 8 pairs of cervical, 12 thoracic, 5 lumbar, 5 sacral, and 1 coccygeal pair of spinal nerves (a total of 31 pairs).

Hence, the correct answer is option 2) 12.

Q3. Identify the following statements.

1) The neural canal is the channel for the spinal cord to pass through.

2) The gray matter extends from the brain to the inside of the spinal cord and white matter covers the surroundings of the spinal cord.

1. Statement 1 is false.

2. Statement 2 is true.

3. Statements 1 and 2 are true

4. Statements 1 and 2 are false.

Correct answer: 3) Statements 1 and 2 are true

Explanation:

Both are true of the spinal cord:
The spinal cord is a long, cylindrical structure running from the back of the brain down to the lower part of the back and through the neural canal. It is an extremely important linkage between the central and peripheral nervous system.
The sensory neurons transmit impulses through the spinal cord. It is the portion that contains grey matter as horn-like projections and white matter surrounding it. Grey matter includes the cell bodies of neurons while white matter consists of myelinated axons connecting to other parts of the nervous system.
The spinal cord carries out the reception of sensory input and coordination of reflexes.

Hence the correct answer is option 3) Statements 1 and 2 are true.

Also Read:

• MCQs on Spinal Cord

• Sympathetic Nervous System

• Central Nervous System

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