BIOL 113 Study Guide - Midterm Guide: Dorsal Root Ganglion, Arachnoid Mater, Pia Mater
Document Summary
Know the meanings of the following terms & locations of structures: Tracts: clusters of myelinated axons within cns (equivalent to pns nerves) Conus medullaris: inferior terminal of spinal cord. Cauda equina: collection of nerve roots leading to the spinal nerves. Filium terminale: fibrous material covered by pia mater; tethers the spinal cord to the coccyx. Spinal nerves: part of the pns; attach to spinal cord by paired roots. Spinal nerve roots: segments extending from the spinal cord. Dorsal/posterior median sulcus: narrow groove on posterior side; smaller indentation. Ventral/anterior median fissure: wide groove on anterior side; larger indentation. Gray commissure: forms the crossbar of h/body of butterfly. Ventral/anterior horn: somatic motor neurons; motor lateral horn: (only in thoracic & lumbar spinal cord): mostly cell bodies of autonomic motor neurons. Decussation: most cross from one side of the body to the other at some point; left to right. Relay: most pathways are a chain of 2-3 neurons.
