Crash Course ANS

• Autonomic nervous system


  Branch of the peripheral nervous system that regulates the functions of internal organs, smooth and cardiac muscles, and glands
• Autonomic nervous system


  • It makes involuntary, fine-tuned adjustments to the body based on signals from the central nervous system
  • It can change body temperature, blood flow, heart rate, and organ secretions
• Sympathetic nervous system


  Division of the autonomic nervous system that prepares the body for activity and the "fight or flight" response
• Parasympathetic nervous system


  Division of the autonomic nervous system that is responsible for "resting and digesting", maintaining the body and conserving energy
• Differences between sympathetic and parasympathetic nervous systems

  • Sympathetic nerves originate in the thoracic and lumbar regions of the spine, while parasympathetic nerves originate in the brain and sacral region
  • Sympathetic ganglia are closer to the spinal cord, while parasympathetic ganglia are closer to the effector organs
  • Sympathetic preganglionic fibers are shorter, while parasympathetic preganglionic fibers are longer
• The sympathetic nervous system is set up to trigger widespread responses to stress, while the parasympathetic system communicates more specifically with individual organs
• The structure of the sympathetic and parasympathetic nervous systems is related to their different functions