We can observe a phenotype whether or not we understand the genetics behind it. In real life, there is a gene called HERC2 that works like I described, and most people with blue eyes have the broken allele of this gene.
Nerves, Neuroglia, and Ganglia. A nerve is a bundle of fibres (axons and/or dendrites) outside the CNS. Neuroglia are cells of the nervous system that help protect and support it. Ganglia are groups of nerve cell bodies lying outside the CNS.
Neuropathy is when nerve damage interferes with the peripheral nervous systemâs (PNSâs) ability to function. When no cause can be determined, it is called idiopathic neuropathy. The PNS carries information from the central nervous system (CNS), or brain and spinal cord, to the rest of the body.