Structure Of Spinal Cord

Explanation
The given information describes the spinal cord. It is approximately 16-18 inches long and is located within the vertebral canal. It ends between the 1st and 2nd lumbar vertebrae. The spinal cord consists of 31 segments and serves as a connection between the central nervous system (CNS) and different parts of the body through the branches of spinal nerves. Therefore, the correct answer is spinal cord.

Explanation
The correct answer is 8 pair. The cervical region of the spinal cord gives rise to eight pairs of cranial nerves. These nerves are responsible for transmitting sensory and motor information between the brain and various parts of the body, including the neck, shoulders, and upper limbs.

Explanation
The thoracic cranial nerves refer to the nerves that originate from the thoracic region of the spinal cord and innervate the muscles and organs of the head and neck. The correct answer is 12 pairs because there are 12 pairs of cranial nerves in total. These nerves are responsible for various functions such as vision, hearing, taste, smell, and motor control of the face and neck muscles.

Explanation
The lumbar region of the spinal cord gives rise to 5 pairs of lumbar cranial nerves. These nerves are responsible for transmitting sensory and motor signals to and from the lower back, hips, and legs. They play a crucial role in controlling muscle movements, sensation, and reflexes in the lower extremities. The lumbar cranial nerves are numbered L1-L5 and contribute to the complex network of nerves that make up the peripheral nervous system.

Explanation
The sacral cranial nerves refer to the nerves that originate from the sacral region of the spinal cord and innervate various structures in the pelvic region. There are a total of 5 pairs of sacral cranial nerves, which include the S1 to S5 nerves. These nerves play a crucial role in controlling bladder and bowel function, as well as sexual function.

Explanation
The correct answer is 1 pair. The coccygeal cranial nerves refer to the nerves that originate from the coccygeal region of the spinal cord. In humans, there is only one pair of coccygeal nerves, known as the coccygeal nerve roots. These nerves are responsible for transmitting sensory and motor signals to and from the coccyx region.

Explanation
The correct answer is "conus medullaris". The conus medullaris refers to the tapered end of the spinal cord, which usually ends at the level of the first or second lumbar vertebra. It is the final portion of the spinal cord before it continues as a bundle of nerves called the cauda equina. The conus medullaris is an important anatomical landmark and is often used as a reference point for spinal cord injuries or spinal procedures.

Explanation
The filum terminale is a non-nervous tissue that arises from the conus medullaris and extends downward to attach to the coccyx. Its main function is to support the spinal cord.

Explanation
The correct answer is cauda equina. The cauda equina is a group of spinal nerves that are located at the lower end of the spinal cord. It consists of the lumbar nerves 3, 4, and 5, pairs of sacral nerves, and one pair of coccygeal nerves. The term "cauda equina" means "horse's tail" in Latin, which is a fitting description for this bundle of nerves that resembles a horse's tail.

Explanation
The correct answer is central canal. The central canal is a canal located at the center of the spinal cord. It is connected to the 4th ventricle of the brain and contains cerebrospinal fluid (CSF).

Explanation
The central canal is a passageway that runs through the center of the spinal cord. It is filled with cerebrospinal fluid and is responsible for carrying nutrients and waste products to and from the spinal cord. The central canal is surrounded by gray matter, which contains cell bodies and is responsible for processing and transmitting information. The white matter, which surrounds the gray matter, is divided into anterior, posterior, and lateral columns, and contains nerve fibers that transmit signals to and from different parts of the body.

Explanation
Funiculi are bundles of myelinated nerve fibers that make up the ascending and descending tracts in the spinal cord. These tracts are responsible for transmitting sensory information from the body to the brain (ascending tracts) and motor commands from the brain to the body (descending tracts). The funiculi provide a pathway for these nerve fibers to travel, allowing for efficient communication between different parts of the nervous system.

Explanation
The statement is true because gray matter, which is found in the central nervous system, does indeed contain anterior, posterior, and lateral horns. These horns are regions within the gray matter that extend outward and are responsible for transmitting and processing information within the spinal cord.