lumbar vertebrae the five vertebrae between the thoracic vertebrae and the sacrum. vertebra magÂ´na the sacrum. odontoid vertebra the second cervical vertebra, or axis. vertebra plaÂ´na a condition of spondylitis in which the body of the vertebra is reduced to a sclerotic disk.
Generally, in the early stages of drowning, very little water enters the lungs: a small amount of water entering the trachea causes a muscular spasm that seals the airway and prevents the passage of both air and water until unconsciousness occurs.
Bodies start to float once the gas from decomposition replaced the  water inside the lungs. It is effected by the depth and temperature  or the water. In warm water it can bâ¦e as soon as 1 to 2 days in 80  degree water, or as much as 14 to 20 days in freezing cold water.