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.
Management of this profile. If you work at Letts Community Fire Department and have the authority to update fire dept. info, you can apply to manage this profile. To find additional fire departments in your region please use the following links: Letts, IA Fire Departments Â» Louisa County, IA Fire Departments Â» Iowa Fire Departments.