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.
Get help from a doctor now âº. OK: Central nervous system-brain & spinal cord Peripheral nervous system-all the nerves that come out from the brain and spinal cord. Within the peripheral nervous system you have 'somatic' and 'visceral' nervous systems. Somatic refers to muscle, skeleton, skin. Visceral refers to internal organs.