BIOL-UA 11 Chapter : C49 - Nervous Systems
Document Summary
Nerve net - a group of interconnected cells found in cnidarians; controls the contraction and expansion of the gastrovascular cavity; lacks clusters of neurons that perform specialized functions. Nerves - bundles of axons from multiple nerve cells; found in more complex animals; fibrous structures that channel and organize information flow along specific routes through the nervous system. Animals with elongated, bilaterally symmetrical bodies have highly specialized nervous systems; exhibit cephalization. In vertebrate cns, functions of brain and spinal cord are tightly coordinated: Brain provides integrative power that underlies complex behavior. Spinal cord conveys information to and from the brain and generates basic patterns of locomotion; also acts independently in reflexes (body"s automatic responses to certain stimuli) Reflexes protect the body by triggering a rapid, involuntary response to a particular reflex. Underlying segmental organization is apparent in the arrangement of neurons within the spinal cord and in the distribution of spinal nerves and ganglia just outside the spinal cord.
