(mÃ»r'kyÉ-rÄ) Symbol Hg. A silvery-white, dense, poisonous metallic element that is a liquid at room temperature and is used in thermometers, barometers, batteries, and pesticides. Atomic number 80; atomic weight 200.59; melting point -38.87Â°C; boiling point 356.58Â°C; specific gravity 13.546 (at 20Â°C); valence 1, 2. See Periodic Table.
Types of vertebra? Vertebrae are divided into sections: the atlas and axis account for the first cervical vertebrae, of which there are 7 in total; there are 12 thoracic vertebrae, 7 lumbar vert â¦ ebrae, 1 sacrum (5 separate vertebrae in a baby), and 1 coccyx (4 separate vertebrae in a baby).here are Five different types of Vertebrae in the Vertabral collumn (spine). 1) Cervical Vertebrae (7) 2) Thoracic Vertebrae (12) 3) Lumbar Vertebrae (5) 4) Sacral Ve â¦ rtebrae (5) 5) Coccygeal Vertebrae (3). + 33 others found this useful. Yerroh Jalloh.
There are 5 major regions of the spine: 1  Cervical: The 7 vertebrae in the neck form the cervical region of the spine. 2  Thoracic: The 12 vertebrae in the chest region form the spineâs thoracic region.  Lumbar: The 5 vertebrae in the lower back form the lumbar region of the spine. Lumbar vertebrae are even larger and stronger than thoracic vertebrae, but are more flexible due to the lack of ribs in the lumbar region. All of the upper bodyâs weight bears down on the lumbar vertebrae, leading to many back problems in this region despite the size and strength of the vertebrae.