Divisions Of The Nervous System

• What are the main components of the nervous system?

  Brain and spinal cord
• What is the primary function of the nervous system?

  Collects, processes information, and directs actions
• What are the two main parts of the nervous system?

  Central nervous system and peripheral nervous system
• What does the central nervous system (CNS) consist of?

  Brain and spinal cord
• What is the role of the spinal cord in the CNS?

  Receives and transmits information to/from the brain
• What is the function of the peripheral nervous system (PNS)?

  Collects sense impressions and delivers instructions
• What type of neurons deliver information to the CNS?

  Sensory or afferent neurons
• What type of neurons transmit information away from the CNS?

  Motor or efferent neurons
• What does the somatic nervous system (SNS) control?

  Skeletal muscles under voluntary control
• What does the autonomic nervous system (ANS) control?

  Internal organs and glands under involuntary control
• What are the two branches of the autonomic nervous system?

  Sympathetic and parasympathetic
• What is the function of the sympathetic nervous system?

  Activates the fight-or-flight response
• What neurotransmitter is released by the sympathetic branch?

  Noradrenaline
• What happens to the body during the fight-or-flight response?

  Heart rate and breathing increase, digestion stops
• What is the function of the parasympathetic nervous system?

  Decreases bodily activities and promotes rest
• What neurotransmitter is released by the parasympathetic branch?

  Acetylcholine
• What is homeostasis?

  Maintaining balance in the internal environment
• How many nerve cells are in the human gut?

  About 100 million
• How does the number of nerve cells in the gut compare to a cat's brain?

  Similar number of nerve cells
• What are the key functions of the nervous system?

  • Collects information from the environment
  • Processes this information
  • Directs actions through electrochemical messages
• How do the sympathetic and parasympathetic systems work together?

  • Sympathetic: Activates fight-or-flight response
  • Parasympathetic: Promotes rest and digestion
  • Together maintain homeostasis in the body