Podcast
Questions and Answers
What primary effectors are influenced by parasympathetic outflow?
What primary effectors are influenced by parasympathetic outflow?
- Blood pressure regulation and thermoregulation
- Fluid exchange and metabolic rate
- Contraction/distension, excretion, and conduction time (correct)
- Hormonal secretion and respiratory rate
How does the concept of homeo-dynamics relate to physiological adaptivity?
How does the concept of homeo-dynamics relate to physiological adaptivity?
- It implies static set points for various body functions.
- It supports the concept of flexible adjustment to varying conditions. (correct)
- It restricts physiological responses to only one type of stimulus.
- It demonstrates the body's inability to adapt to environmental changes.
What characterizes the interactions at the peripheral level within the autonomic nervous system?
What characterizes the interactions at the peripheral level within the autonomic nervous system?
- Interactions are linear and predictable in nature.
- Controlled variables interact with other controlled variables, influencing regulation. (correct)
- They operate solely based on fixed individual set points.
- They are entirely independent of central nervous system modulation.
Which of the following best describes the parasympathetic and sympathetic systems in terms of their effects?
Which of the following best describes the parasympathetic and sympathetic systems in terms of their effects?
Which factor is NOT a characteristic of the neural pathways in the autonomic nervous system?
Which factor is NOT a characteristic of the neural pathways in the autonomic nervous system?
Which aspect of autonomic regulation is likely related to the absence of fixed set-points?
Which aspect of autonomic regulation is likely related to the absence of fixed set-points?
In what way does the concept of self-organization play a role in the autonomic nervous system?
In what way does the concept of self-organization play a role in the autonomic nervous system?
Which of the following statements about the fight-or-flight response is accurate?
Which of the following statements about the fight-or-flight response is accurate?
Which physiological change is typically associated with sympathetic nervous system activation?
Which physiological change is typically associated with sympathetic nervous system activation?
What happens to respiratory frequency during a sympathetic response?
What happens to respiratory frequency during a sympathetic response?
Which effect is NOT a direct result of sympathetic activation?
Which effect is NOT a direct result of sympathetic activation?
In a sympathetic response, what is the effect on blood flow to the skin?
In a sympathetic response, what is the effect on blood flow to the skin?
What role does the parasympathetic nervous system primarily play in contrast to the sympathetic system?
What role does the parasympathetic nervous system primarily play in contrast to the sympathetic system?
Which of the following best describes the balance between sympathetic and parasympathetic activities?
Which of the following best describes the balance between sympathetic and parasympathetic activities?
How does sympathetic nervous system activation affect glucose metabolism?
How does sympathetic nervous system activation affect glucose metabolism?
Which of the following statements about hair erection during a sympathetic response is true?
Which of the following statements about hair erection during a sympathetic response is true?
What is the origin of preganglionic neurons in the sympathetic nervous system?
What is the origin of preganglionic neurons in the sympathetic nervous system?
Which cranial nerve predominantly carries parasympathetic preganglionic fibers?
Which cranial nerve predominantly carries parasympathetic preganglionic fibers?
What is the primary function of the sympathetic nervous system during a 'fight or flight' response?
What is the primary function of the sympathetic nervous system during a 'fight or flight' response?
Where are sympathetic postganglionic neuron bodies primarily located?
Where are sympathetic postganglionic neuron bodies primarily located?
What characterizes the postganglionic fibers of the parasympathetic nervous system?
What characterizes the postganglionic fibers of the parasympathetic nervous system?
How does the adrenal medulla function concerning the sympathetic nervous system?
How does the adrenal medulla function concerning the sympathetic nervous system?
What role does the balance between sympathetic and parasympathetic activities play?
What role does the balance between sympathetic and parasympathetic activities play?
Which of the following statements about the paravertebral chain of the sympathetic system is incorrect?
Which of the following statements about the paravertebral chain of the sympathetic system is incorrect?
Flashcards are hidden until you start studying
Study Notes
Parasympathetic Outflow
- Originates from the medulla along cranial nerve X (vagus) to ganglia at target organs.
- Effects include contraction/distension, excretion, modulation of conduction time, and fluid/gas exchange.
General Characteristics of Autonomic Regulation
- Achieves homeostasis at cellular level, requiring adaptability at physiological system level.
- "Homeo-dynamics" refers to the adjustment of physiological parameters based on activity and environmental needs.
- Both afferent and efferent pathways demonstrate generalized parallelism.
- Peripheral level interactions involve controlled variables that are interconnected within distributed systems (e.g., arterial system, digestive tract).
- Central level interactions involve regulatory activities influencing and being influenced by one another.
- Target organs exhibit intrinsic regulation, receiving additional autonomic control.
- Regulation is hierarchical, occurring at multiple levels.
- Non-linearity leads to self-organization, versatility, and adaptability but can also result in pathological behaviors.
Sympathetic vs Parasympathetic
- Sympathetic and parasympathetic systems often have opposing effects (e.g., symp.vagal balance affecting heart function).
Autonomic Nervous System Functional Anatomy
- Sympathetic system has thoracolumbar centers, whereas the parasympathetic system has brainstem and sacral spinal centers.
- Preganglionic neuron bodies:
- Sympathetic in thoraco-lumbar spinal cord (T1-T12, L1-L2).
- Parasympathetic in brainstem and sacral spinal cord.
- Sympathetic (post) ganglionic fibers arise from ganglia near the spine:
- Paravertebral chain and prevertebral ganglia (e.g., celiac, mesenteric).
- Paravertebral chain extends across all spinal segments, influencing multiple visceral functions.
- Adrenal medulla acts as a modified sympathetic ganglion, releasing neurotransmitters directly into the bloodstream.
- Parasympathetic fibers primarily travel via the vagus nerve to target organ ganglia, resulting in very short postganglionic fibers.
Sympathetic System Responses
- Triggers "fight/flight/fright" reactions characterized by increases in:
- Heart rate, arterial pressure, cardiac contractility, conduction velocity.
- Bronchial dilation, respiratory frequency, pupil dilation.
- Muscle vessel dilation, sweating, and glucose metabolism.
- Decreases in:
- Digestive motility, excretion, salivation, and skin blood flow.
Notable Observations
- Only skin and peripheral vessel regulation is purely sympathetic; otherwise, sympathetic actions are typically countered by parasympathetic effects.
- Effects on specific systems include:
- Heart: Increases (sympathetic) vs Decreases (parasympathetic).
- Respiratory: Increases in frequency and dilation (sympathetic) vs Decreases (parasympathetic).
- Vision: Pupil dilation (sympathetic) vs No effect (parasympathetic).
- Digestive: Decreases in motility/excretion (sympathetic) vs Increases (parasympathetic).
- "Horripilation" refers to hair erection (goosebumps) during emotional or frightening situations.
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
