A ganglion is a cluster of nerve cell bodies located in the peripheral nervous system. These structures play a crucial role in transmitting signals between the central nervous system and various parts of the body. Ganglia can be found in various locations, including near the spinal cord and within certain organs. In addition to their role in nerve signal transmission, ganglia can also be involved in reflex actions and autonomic functions. For example, the dorsal root ganglia contain sensory neurons that relay information from the body to the spinal cord. Understanding ganglia is essential for studying the nervous system and its functions.