CogKnoSys

Knowledge you can walk. Read the idea below, then step up to the general, across to peers or down to the specific.

Physical

Spinal Column

The spinal column, or backbone, is a stack of bones called vertebrae that surrounds and protects the spinal cord.

Learn, discuss, create, buy or invest

The idea

The spinal column, also called the vertebral column, spine or backbone, is the central part of the skeleton in animals with backbones. It is so important that vertebrates are named after it. Around 50,000 species of animals have one.

The column is a stack of bones called vertebrae. Between the vertebrae sit cushions called intervertebral discs, which form cartilage joints that let the spine bend. Along the back of the column runs the spinal canal, a tunnel that encloses and protects the spinal cord. Spinal nerves leave the canal through small gaps between the vertebrae and reach each part of the body.

Vertebrae are named for the body region they sit in: the neck, chest, abdomen, pelvis or tail. Human vertebrae are fairly typical of those in other mammals, reptiles and birds, though the shape of the main bone varies between groups. Doctors use bony features of the vertebrae as landmarks to guide procedures such as spinal anesthesia. Spina bifida is the most common birth defect that affects the spinal column.

Check yourself

Question 1 of 2

Roughly how many animal species have a vertebral column?

Pick one. The first pick counts.

Composition

what it's made of

  • Vertebrae — The individual bones stacked to form the column.
  • Intervertebral Discs — Cartilage pads between the vertebrae that cushion them and allow movement.
  • Spinal Canal — A tunnel formed by the lined-up arches of the vertebrae that protects the spinal cord.
  • Spinal Nerves — Nerves that exit through gaps between vertebrae to serve each body segment.
  • Spinous Processes — Bony ridges on the back of the vertebrae that can be felt through the skin and serve as landmarks.

Connection

how it relates

Under Skeletal System

In place

  1. Central Nervous Systemstrength 80 of 100

    The spinal column encloses and protects the spinal cord, part of the central nervous system.

  2. Peripheral Nervous Systemstrength 60 of 100

    Spinal nerves of the peripheral nervous system leave through gaps between the vertebrae.

Related

  1. Skeletal Musclestrength 50 of 100

    Back muscles attach to the vertebrae and hold the spine upright while letting it bend and twist.

Change

how and why it evolves

Past
The backbone evolved in the ancestors of fish and was passed down to amphibians, reptiles, birds and mammals.
Now
Today the human spine is one of the most-studied backbones, and medicine treats spinal conditions such as scoliosis, kyphosis and worn-out discs.
Next
Better imaging and surgery will likely improve care for back pain and spinal injuries, while the spine's basic design stays the same.

Knowledge you can walk. Read the idea, then step up, across or down.

Spinal Column

The spinal column, or backbone, is a stack of bones called vertebrae that surrounds and protects the spinal cord.

Learn, discuss, create, buy or invest

The idea

The spinal column, also called the vertebral column, spine or backbone, is the central part of the skeleton in animals with backbones. It is so important that vertebrates are named after it. Around 50,000 species of animals have one.

The column is a stack of bones called vertebrae. Between the vertebrae sit cushions called intervertebral discs, which form cartilage joints that let the spine bend. Along the back of the column runs the spinal canal, a tunnel that encloses and protects the spinal cord. Spinal nerves leave the canal through small gaps between the vertebrae and reach each part of the body.

Vertebrae are named for the body region they sit in: the neck, chest, abdomen, pelvis or tail. Human vertebrae are fairly typical of those in other mammals, reptiles and birds, though the shape of the main bone varies between groups. Doctors use bony features of the vertebrae as landmarks to guide procedures such as spinal anesthesia. Spina bifida is the most common birth defect that affects the spinal column.

Check yourself

2 quick questions, instant feedback.