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.
Des Moines County is part of the Burlington, IAâIL Micropolitan Statistical Area. Des Moines County should not be confused with the city of Des Moines, which is the capital of Iowa. Des Moines County sits on Iowa's eastern border alongside the Mississippi River. The city of Des Moines is in Polk County in south-central Iowa. Both places derive their name from the Des Moines River, which flows through both the city and the county.