The sympathetic division of the ANS prepares the body for stress, physical activity, and increased energy demands. Its preganglionic fibers originate in the thoracic and lumbar spinal cord segments. The fibers leave the spinal cord through the white ramus communicans and enter the sympathetic chain ganglion. They then synapse with postganglionic fibers at three possible locations: within the sympathetic chain ganglia, at one of the collateral ganglia, or in the adrenal medullae. The sympathetic chain ganglia are a series of interconnected ganglia located bilaterally along the spinal cord. Their neurons regulate various organs, including blood vessels, sweat glands, and visceral organs. The collateral ganglia are positioned anteriorly to the spinal cord. Their neurons innervate organs in the abdominopelvic region. The adrenal medulla is located inside the adrenal gland. When stimulated, it releases neurotransmitters in the bloodstream. These neurotransmitters act as hormones, regulating the activity of distant cells. Because the ganglia lie close to the spinal cord, the sympathetic division has short preganglionic and long postganglionic fibers.