Question

part a assessments
complete the following statements:

1. the vertebral column encloses and protects the spinal cord a
2. the number of separate bones in the vertebral column of an adult is 26 a
3. the bodies of the vertebrae support the weight of the head and trunk. a
4. the intervertebral foramina provide passageways for spinal nerves a
5. transverse foramina of cervical vertebrae serve as passageways for vertebral arteries leading to the brain. a
6. the first vertebra is also called the atlas a
7. the second vertebra is also called the axis a
8. when the head is moved from side to side, the first vertebra pivots around the axis of the second vertebra. a
9. the lumbar vertebrae have the largest and strongest bodies. a
10. the typical number of vertebrae that fuse in the adult to form the sacrum is 5 a
11. the upper, anterior margin of the sacrum that projects forward is called the sacral promontary a
12. an opening called the sacral exists at the tip of the sacral canal. a

part b assessments
based on your observations, compare typical cervical, thoracic, and lumbar vertebrae in relation to the characteristics stated in the table. the table is partly completed. for your responses, consider characteristics such as size, shape, presence or absence, and unique features. a a

vertebra	number	size	body	spinous process	transverse foramina
thoracic	12	intermediate	medium	long, slender	absent
lumbar	5	largest	largest	short, blunt	absent

Explanation:

1. The vertebral column protects the spinal cord. There are 26 separate bones in an adult's vertebral column. The bodies of vertebrae support head and trunk weight. Intervertebral foramina are for spinal nerves, and transverse foramina of cervical vertebrae are for vertebral arteries. The first vertebra is the atlas, the second is the axis, and the atlas pivots around the axis for side - to - side head movement. Lumbar vertebrae have the largest and strongest bodies. Five vertebrae fuse to form the sacrum, with its anterior margin called the sacral promontory and an opening at the tip of the sacral canal called the sacral hiatus.
2. For the comparison: Cervical vertebrae are 7 in number, small in size, with the smallest body, C2 - C6 have bifid spinous processes and transverse foramina are present. Thoracic vertebrae are 12, intermediate in size, with a medium - sized body, long and slender spinous processes, and no transverse foramina. Lumbar vertebrae are 5, the largest in size, with the largest body, short and blunt spinous processes, and no transverse foramina.

Answer:

1.

• The vertebral column encloses and protects the spinal cord.
• The number of separate bones in the vertebral column of an adult is 26.
• The bodies of the vertebrae support the weight of the head and trunk.
• The intervertebral foramina provide passageways for spinal nerves.
• Transverse foramina of cervical vertebrae serve as passageways for vertebral arteries leading to the brain.
• The first vertebra is also called the atlas.
• The second vertebra is also called the axis.
• When the head is moved from side to side, the first vertebra pivots around the axis of the second vertebra.
• The lumbar vertebrae have the largest and strongest bodies.
• The typical number of vertebrae that fuse in the adult to form the sacrum is 5.
• The upper, anterior margin of the sacrum that projects forward is called the sacral promontory.
• An opening called the sacral hiatus exists at the tip of the sacral canal.

2.

• Cervical: Number - 7, Size - Small, Body - Smallest, Spinous Process - C2 through C6 are forked (bifid), Transverse Foramina - Present
• Thoracic: Number - 12, Size - Intermediate, Body - Medium, Spinous Process - Long, slender, Transverse Foramina - Absent
• Lumbar: Number - 5, Size - Largest, Body - Largest, Spinous Process - Short, blunt, Transverse Foramina - Absent