It is called hydrosphere
It is the total water in Earth.
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Twelve pairs of ribs are attach to the second spinal region which is called the thoracic. Thoracic spine is kyphotic. Kyphotic means excessive curvature of the spine as it occurs in thoracic and also sacral regions. Thoracic spine is located in the chest area.The ribs are attach to the thoracic spine and protect the vital organs that is located thoracic spine region.
