The 8th vertebra of a frog is known as the amphicoelous vertebra since its centrum is biconcave.

Each vertebra has a body, also known as a vertebral body, that is made up of a posterior vertebral arch, also known as a neural arch, and a massive anterior central section called the centrum (vertebral centrum).

The atlas or cervical, the first vertebra in the frog, is ring-shaped to protect the head. The second to seventh vertebrae are procoelous, having extended transverse projections. The posterior end of the urostyle is connected to the eighth vertebra, which is amphicoelous (biconcave), and the ninth vertebra, which is biconvex.

Related Links:

• Frogs – Morphology and Anatomy
• Vertebrae – Bones, Diagram and Features

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