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.
Johnson County is the bluest county in Iowa, with 66.9% of the countyâs vote going to Obama in 2012. As in the bluest counties in many states, Johnson County voters overwhelmingly vote for Democrats in congressional elections. The county sent only democrats to the House in each of the last 10 years.