BIOB34H3 Chapter : BIOB30 Ch8 (247-258).docx
Document Summary
The brain and spinal cord are integrating centers for homeostasis, movement and many other body functions. Nervous system a network of billions or trillions of nerve cells linked together in a highly organized manner to form the rapid control system of the body: controlled by the brain and spinal cord. Neurons uniquely shaped cells that carry electrical signals rapidly and, sometimes, over long distances: also called nerve cells, processes long thin extensions possessed by some neurons. Can extend up to a meter in length. Neurotransmitters chemical signals released into the extracellular fluid by most neurons: alternative: gap functions links between neurons that allow electrical signals to pass directly from cell to cell. Single-celled protozoa and plants also use electrical signaling mechanisms similarly. Emergent properties complex processes that cannot be predicted from what we know about the properties of individual nerve cells: nervous system examples: consciousness, intelligence, emotion.
