There are ___(i)___pairs of spinal nerves and ___(ii)___pairs of cranial nerves in human being.

In human beings, there are 31 pairs of spinal nerves and 12 pairs of cranial nerves.

Explanation

1. Spinal Nerves: The 31 pairs of spinal nerves arise from the spinal cord and are organized into segments: 8 cervical, 12 thoracic, 5 lumbar, 5 sacral, and 1 coccygeal. These nerves are responsible for transmitting signals between the spinal cord and the rest of the body, controlling both voluntary and involuntary actions.

2. Cranial Nerves: The 12 pairs of cranial nerves emerge directly from the brain and brainstem, primarily involved in sensory and motor functions of the head and neck. Each cranial nerve has a specific function, such as vision, hearing, taste, and controlling facial movements.

Summary

• (i) 31 pairs of spinal nerves
• (ii) 12 pairs of cranial nerves