The Autonomic Nervous System Overview
10 Questions
4 Views

Choose a study mode

Play Quiz
Study Flashcards
Spaced Repetition
Chat to lesson

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

Which division of the autonomic nervous system typically increases heart rate?

  • Parasympathetic Division
  • Sympathetic Division (correct)
  • Somatic Division
  • Entropic Division
  • What type of receptors are primarily engaged by autonomic sensory neurons to monitor internal conditions?

  • Photoreceptors
  • Thermoreceptors
  • Interoceptors (correct)
  • Exteroceptors
  • Which part of the body regulates autonomic nervous system reflexes?

  • Spinal Cord
  • Cerebellum
  • Hypothalamus and Brain Stem (correct)
  • Cerebrum
  • Which nervous system is NOT a division of the peripheral nervous system?

    <p>Sensory Nervous System</p> Signup and view all the answers

    What is the role of autonomic motor neurons in the autonomic nervous system?

    <p>They propagate impulses to effector tissues.</p> Signup and view all the answers

    What is the role of the preganglionic neuron in the autonomic motor pathway?

    <p>It synapses with postganglionic neurons in autonomic ganglia.</p> Signup and view all the answers

    Which of the following statements best describes the difference between somatic and autonomic motor neurons?

    <p>Somatic motor neurons release acetylcholine, while autonomic neurons can release either acetylcholine or norepinephrine.</p> Signup and view all the answers

    What structural feature differentiates postganglionic neurons from preganglionic neurons?

    <p>Postganglionic neurons have axons that are unmyelinated fibers.</p> Signup and view all the answers

    Which type of muscle continues to contract rhythmically even if its nerve supply is damaged?

    <p>Smooth muscle in the gastrointestinal tract</p> Signup and view all the answers

    In which situation do preganglionic neurons synapse with specialized cells rather than an autonomic ganglion?

    <p>When regulating endocrine secretions.</p> Signup and view all the answers

    Study Notes

    The Autonomic Nervous System and Homeostasis

    • The autonomic nervous system (ANS) regulates involuntary functions like smooth muscle, cardiac muscle, and gland activity.
    • The ANS operates via reflex arcs, with two divisions: sympathetic and parasympathetic.
    • Most body organs have dual innervation, meaning they receive input from both the sympathetic and parasympathetic systems.
    • Autonomic motor pathways have two neurons: preganglionic and postganglionic.
    • Preganglionic neurons originate in the brain or spinal cord and synapse with postganglionic neurons in autonomic ganglia.
    • Interoceptors: Sensory receptors in blood vessels, visceral organs, muscles, and the nervous system monitor internal conditions.

    Anatomy of Autonomic Motor Pathways

    • Sympathetic Division (Thoracolumbar Division):

      • Preganglionic neurons originate in the spinal cord's thoracic and upper lumbar segments (T1-L2).
      • Sympathetic ganglia are located along the spinal cord (sympathetic trunk ganglia) or near major abdominal arteries (prevertebral ganglia).
      • Short preganglionic axons and long postganglionic axons.
    • Parasympathetic Division (Craniosacral Division):

      • Preganglionic neurons originate in the brainstem and sacral spinal cord segments (S2-S4).
      • Parasympathetic ganglia are located near or within the target organs.
      • Long preganglionic axons and short postganglionic axons.
    • Neurotransmitters:

      • Preganglionic neurons in both divisions release acetylcholine (ACh).
      • Postganglionic neurons of the sympathetic division mostly release norepinephrine (NE).
      • Postganglionic neurons of the parasympathetic division release acetylcholine (ACh).

    Sympathetic Responses (Fight-or-Flight)

    • General effects: Increased alertness, heart rate, blood pressure, breathing, and blood flow to skeletal muscles. Decreased blood flow to digestive organs, and urine production.
    • Pupil dilation
    • Bronchodilation (widening of airways)
    • Increased heart rate and force of contraction
    • Glycogenolysis (breakdown of glycogen into glucose)
    • Lipolysis (breakdown of triglycerides into fatty acids)
    • Increased blood glucose levels
    • Inhibition of digestive activities

    Parasympathetic Responses (Rest-and-Digest)

    • General effects: Promotes relaxation, digestion, and energy conservation.
    • Increased salivation, lacrimation, urination, digestion, and defecation (SLUDD)
    • Pupil constriction
    • Decreased heart rate
    • Bronchoconstriction (narrowing of airways)

    Additional Notes

    • Dual Innervation: Most organs receive both sympathetic and parasympathetic input.
    • Hypothalamus: Plays a major role in regulating the ANS.
    • Adrenal Medulla: Secretes epinephrine and norepinephrine, enhancing and prolonging sympathetic responses.
    • Somatic vs. Autonomic Nervous System: The somatic nervous system controls voluntary muscle movement, while the autonomic nervous system controls involuntary functions.

    Studying That Suits You

    Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

    Quiz Team

    Related Documents

    Description

    Explore the intricacies of the autonomic nervous system, including its structure, function, and role in homeostasis. Understand the sympathetic and parasympathetic divisions along with the pathways involved in autonomic motor function. This quiz will help reinforce your knowledge of the ANS and its impact on involuntary bodily functions.

    More Like This

    Use Quizgecko on...
    Browser
    Browser