Nervous System. All mental and physical activities are controlled or mediated by the brain and the nervous system. Voluntary actions originate in the brain and the nerves carry the information to other parts of our body.The nervous system relies upon a correct chemical balance in the body.ervous System. All mental and physical activities are controlled or mediated by the brain and the nervous system. Voluntary actions originate in the brain and the nerves carry the information to other parts of our body.
From Wikipedia, the free encyclopedia. Letts is a city in Louisa County, Iowa, United States established in 1855. The population was 384 at the 2010 census. It is part of the Muscatine Micropolitan Statistical Area. The name is from local benefactor, Maddison Letts.
Livingston County is located in the Finger Lakes region, south of Rochester and east of Buffalo.Letchworth State Park in partly in the western part of the county. The Genesee River flows northward through the county.