pairs of spinal nerves originate in the spinal cord, carrying bundles of sensory and motor neurons throughout the body.

pairs of spinal nerves originate in the spinal cord, carrying bundles of sensory and motor neurons throughout the body.

The answer is "31"

Explanation:

Neurons are nerve cells that are specialized to process and transmit information.

The spinal cord acts as a nerve center between the brain and the rest of our body and it contains motor neurons that transmits nerve signals from the motor cortex to the body, and the spinal cord also receives all of the sensory information from the periphery of our bodies.

Motor neurons are also known as efferent neurons, they are part of the central nervous system that transmit impulses from the brain or spinal cord to the effector organ (muscles or glands).

Sensory neurons are also known as afferent neurons, they are nerve cells within the nervous system responsible for conducting nerve impulses from the body to the brain or spinal cord.

The spinal nerves are part of the peripheral nervous system and it contains the fibers of the sensory and motor neurons. Humans have 31 left–right pairs of spinal nerves which is formed by the combination of nerve fibers from the dorsal and ventral roots of the spinal cord. There are 31 segments in the spinal cord: 1 coccygeal, 12 thoracic,  8 cervical, 5 sacral, and 5 lumbar. The spinal nerve send motor, sensory, and autonomic signals between the central nervous system and the body. The spinal nerves are  labelled by their location in the body: thoracic, lumbar, or sacral. Each spinal nerve emerges in two short branches (roots): one at the front, which is the motor root of the spinal cord, and one at the back, which is the sensory root of the spinal cord.

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