The human spine consists of 33 bones, and the bones that make up the spine are called vertebrae. The top of the spine is embedded in the skull, and the end is connected with the pelvis to support the whole bone.

Vertebra is divided into -7 cervical vertebra, 12 vertebra, 5 lumbar vertebra and 5 sacrum in different parts, which are fused into one bone and 4 coccyx in adulthood and integrated into a whole in adulthood, totaling 33. The spine is connected with the spine through a plane joint.

With these joints, we can bend back, turn left, turn right, bend forward and touch our toes with our hands.

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